Although 0 dB is often referred to as the lower threshold of human hearing, it is important to realize that the human ear is not equally sensitive to all frequencies of sound. In other words, a particular noise may sound louder or softer depending on the frequency of the sound wave being transmitted. Because of this variation, scientists have defined a unit of loudness, called a phon, to represent the intensity of sound waves with a frequency of 1000 Hz. A 60-phon sound is one that is perceived by the human ear to have the same loudness as a sound wave with an intensity of 60 dB and a frequency of 1000 Hz.

Required:
a. At approximately what frequency do most people perceive the least intense sounds? Answer numerically in hertz to two significant figures.
b. Normal conversation has a sound level of about 60 dB. How many times more intense must a 100-Hz sound be compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness?

Answers

Answer 1

Answer:

20 Hz

15.8 times

Explanation:

A

Although the range of frequency for any human's ear is usually said to be between 20 Hz and 20 kHz. And since the question asked for the least intense frequency, that has to be 20 Hz. Essentially the frequency most people perceive the least intense sound is 20 Hz.

B

A 100-Hz sound must be 10^1.2 times or 15.8 times more intense compared to a 1000-Hz sound to be perceived as equal to 60 phons of loudness


Related Questions

5) A 1200 kg racecar starts from rest and has a velocity of 35 m/s over a distance of 100 m. What is
the net force on the racecar?

Answers

F = - 600 N is the net force on the racecar .

What is acceleration ?

Acceleration is a measure of how quickly an object changes its velocity, or the rate at which its velocity changes over time. It is a vector quantity, which means it has both magnitude and direction. In physics, acceleration is usually defined as the change in velocity per unit time, and is expressed in units of meters per second squared (m/s^2). Acceleration can result from a change in speed, direction, or both. Objects that are accelerating are said to be undergoing a net force, and their acceleration is proportional to the magnitude of the force and inversely proportional to their mass.

Rate of change of momentum = net force acting on the object …………

m Vf - m Vi / t = net force acting on the object

m (Vf - Vi / t) = F

1200 ( 0 - 10 /20) = - 600 N = F

so, net force acting on the object =

F = - 600 N

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A certain electric dipole consists of charges + and − separated by distance , oriented along the -axis as shown in the figure. Find an expression for the magnitude of the electric field of the dipole at a point far away in the -direction, a distance away from the midpoint of the dipole. Assume that is much greater than . Enter your answer in terms of , , , and 0.

I've seen other questions like this but the answers are coming back as incorrect or they have it with k included. Please help!

Answers

The magnitude of the electric field of the dipole at a point far away in the -direction, a distance away from the midpoint of the dipole is given by

|E| = |-(p * k) / r^3|

What is magnitude of the electric field?

Generally, The electric field of an electric dipole at a point far away from the midpoint of the dipole is given by the following expression:

E = (p * k) / r^3 * (3 *cos(theta) * i^ + sin(theta) * j^)

where:

p is the magnitude of the dipole moment, equal to q * d (q is the charge and d is the distance between the charges)

k is the Coulomb constant (9 x 10^9 N * m^2/C^2)

r is the distance from the dipole to the point where the electric field

is being calculated theta is the angle between the vector pointing from the dipole to the point where the electric field is being calculated and the dipole moment vector (in this case, the -axis) i^ and j^ are the unit vectors in the x and y directions, respectively.

Since the dipole is oriented along the -axis and the point where the electric field is being calculated is far away in the -direction,

theta = pi and the expression for the electric field becomes:

E = (p * k) / r^3 * (3 *cos(pi) * i^ + sin(pi) * j^)

E = -(p * k) / r^3 * (i^)

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If there is going to be a total lunar eclipse tonight, then you know that:
If there is going to be a total lunar eclipse tonight, then you know that:
the Moon's phase is full.
the Moon's phase is new.
the Moon is unusually close to Earth.

Answers

The correct option about total lunar eclipse is that the moon's phase is full and the moon is unusually close to Earth.

Moon is also known as satellite of earth and revolves around the Earth. Earth is the planet that revolves around the sun. When the moon is unusually close to Earth such that it crosses the Earth's orbital plane, it is results in lunar eclipse.

The mentioned two points in answers the conditions that must be fulfilled for a lunar eclipse to occur.

The condition of moon phase to be new is important and required in the case of solar eclipse. Another required point is close proximity of moon and earth as stated above for lunar eclipse.

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when [s] = 20 km, what percentage (%) of vmax has been reached?

Answers

When s=20km the percentage of vmax reached is 83.33%.

As per the data given in the above question are as bellow,

The data share are as bellow,

The value of s is equal to 20km.

We have to determine the percentage of vmax reached.

We have to use the formula of rate of energy catayzed reaction.

A appropriate catalyst can be added to a reaction to accelerate its pace. A catalyst is a material that speeds up a chemical process without being consumed (remains chemically unchanged at the end). It offers a different, lower-activation-energy reaction route.

Rate of energy calculate reaction is equal to vmax upon km plus s

V=(vmax[s])/(KM+[s])

V=[tex]\frac{vmax\:5Km}{Km+5km}[/tex]

V=[tex]\frac{5vmax\:Km}{6km}[/tex]

Cancelling Km we get,

V=[tex]\frac{5}{6} vmax[/tex]

Percentage of Vmax reached [tex]\frac{\frac{5}{6}vmax }{vmax} \times 100[/tex]

83.33%

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How many electrons are needed to form a charge of
−4.70 nC

Answers

Q = -4.70 nC = -4.70 × 10⁻⁹ C

e = -1.602 × 10⁻¹⁹ C

N: number of electrons

Ne = Q → N = Q/e
N = (4.70/1.602) × 10⁻⁹ × 10¹⁹
= 2.934 × 10¹⁰

"2.934 × 10¹⁰ electrons are require to form a charge of -4.70 nC"

By definition, which of the following can be broken down into simpler substances? a: liquid b: solid c: compound d: atom ion

Answers

Correct option is C, Compound can be broken down into simpler substances.

Additionally, compounds can be divided into more basic components. While some elements only have one letter as their symbol, some have two. A formula is what we create when we represent a compound with symbols. For instance, table salt is a substance consisting of one sodium (Na) and one chlorine (Cl) atom (Cl).

Simpler substances cannot be created from elements. When a compound is broken down, two or more simpler compounds result. Elements are pure substances, 113 of which are recognized. Millions of chemicals exist. Each water molecule is made up chemically of two hydrogen and one oxygen atoms. Only chemical processes can break down water into its constituent parts. Features that make it possible to identify one type of substance from another

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a 2.4×105−kg airplane is cruising at 900 km/h.

Answers

A 2.4×105−kg airplane is cruising at 900 km/h will be 6.48 × 10^10J.

What is airplane?
An airplane is a powered, fixed-wing aircraft that is propelled forward by thrust from an engine. Airplanes come in a variety of sizes, shapes, and wing configurations. The wings, engines, and tail are the three main components of an airplane. The wings provide lift, the engines provide thrust, and the tail provides control and stability. When an airplane is in flight, the wings generate lift, the engines generate thrust, and the tail keeps the airplane balanced and flying straight. Airplanes are used for a variety of purposes, including passenger and cargo transportation, military operations, and recreational activities.

The kinetic energy of the airplane is:

KE = 1/2 mv2 = 1/2 (2.4 × 10^5)(900)^2

= 6.48 × 10^10 J

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what is the q value for the reaction 9be + α → 12c + n

Answers

The Q value for the reaction 9be + α → 12c + n is 4.68 Mev. The amount of energy absorbed or released during a nuclear reaction is known as the Q value for that reaction.

It is a measurement parameter by which we can describe it is exothermic or endothermic. If Q value is -ve then endothermic if +ve then exothermic

[tex]Q_{value}=(m_{r}- m_{p})931 .5~MeV[/tex]

where  

[tex]m_{p} = sum ~of ~masses~ of~ products\\\\m_{r}= sum ~of~ masses~ of ~reactants[/tex]  

Mass of reactants = Mass of Be + Mass of He

                                =9.0121+4.0015

                               = 13.0136 u

Mass of products = Mass of C + Mass of H  

                               =  12+1.0086

                                =13.0086 u

   Q={(13.0136)-(13.0086)(931.5}  

  Q=4.68 MeV

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Image intensifiers used in night-vision devices create a bright image from dim light by letting the light first fall on a photocathode. Electrons emitted by the photoelectric effect are accelerated and then strike a phosphorescent screen, causing it to glow more brightly than the original scene. Recent devices are sensitive to wavelengths as long as 900 , in the infrared: Part A If the threshold wavelength is 900 , what is the work function of the photocathode? Part B If light of wavelength 600 strikes such a photocathode, what will be the maximum kinetic energy, in , of the emitted electrons?

Answers

The work function of the photocathode is 1.38ev.,  The value of maximum kinetic energy is 1.174 ev.

Work function = hc/λ

Where h = plank's constant

c = speed of light

λ = wavelength of light

⇒ (6.63 × 10⁻³⁴ × 3 × 10⁸) / 900 × 10⁻⁹

⇒  1.38ev                                                     ......(1)

∴ The work function of the photocathode is 1.38ev.

Max Kinetic energy = hν - hν₀

From (1)

⇒ 1.38 - 6.63 × 10⁻³⁴ × 3 × 10⁸ / 600 × 10⁻⁹

⇒  1.38    - 0.33 × 10 ⁻¹⁹

⇒  1.38 - 0.206ev

⇒ 1.174 ev

The value of maximum kinetic energy is 1.174 ev.

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The magnitude of charge A is half the magnitude of charge B. However, the electrostatic force experienced by charge A and by charge B is the same. It can be concluded that the electric field strength of charge A is ________ the electric field strength of charge B. one-fourth one-half two times four times

Answers

Answer:

Qb = 2 Qa         magnitude of charge on B is twice that of A

F = K Qa * Qb / R^2   both charges experience the same force

Ea = K Qa / s^2       field strength of A at distance S

Eb = K Qb / s^2       field strength of B at distance S

The electric field strength of B  is twice that of A

That means that charge on A is 1/2 that on B for the forces on each to be the same:

Fa = Qa * Eb

Fb = Qb * Ea

there are two types of cellular phones: handheld phones (h) that you carry and mobile phones (m) that are mounted in vehicles. phone calls can be classified by the traveling speed of the user as fast (f) or slow (w). monitor a cellular phone call and observe the type of telephone and the speed of the user. the probability model for this experiment has the following information: p(f)

Answers

The sequential answer is :A) P(W) = 0.5 and B) P(MF) = 0.3 and C) P(H) = 0.6.

What are cellular phone ?

A mobile phone[a] is a portable telephone that allows users to place and receive calls while on the go inside of a phone service area via a radio frequency link. The radio frequency link creates a connection to a mobile phone operator's switching systems, granting access to the public switched telephone network (PSTN). In North America, mobile phones are referred to as cell phones or cellular telephones since modern mobile telephone services use a cellular network design. Digital mobile phones are capable of a wide range of other services in addition to voice calling, including text messaging, multimedia messaging, email, Internet access (via LTE, 5G NR, or Wi-Fi), short-range wireless communications (infrared, Bluetooth), satellite access (navigation, messaging connectivity), business applications, video games, and digital photography.

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g during forced exhalation, such as when blowing up a balloon, the diaphragm and chest muscles create a pressure of 60.0 mm hg between the lungs and chest wall.

Answers

The force in newtons this pressure creates on the 600 cm2 surface area of the diaphragm is 4.802 N.

P =60.0mm×133.3pa/1mm hg = 7998.

= 600/100² = 0.06

= 7998×0.06= 4.802N.

Stress is the force applied perpendicular to the surface of an object in keeping with the unit location over which that force is shipped. Gauge strain is the strain relative to the ambient strain. Numerous gadgets are used for the specific strain. strain is defined to be the quantity of pressure exerted per location.

The pascal (Pa) is the same old unit of stress. A pascal is a very small quantity of stress, so the most beneficial unit for normal gasoline pressures is the kilopascal (kPa). A kilopascal is equal to a thousand pascals. Another usually used unit of pressure is the atmosphere (atm).strain is commonly measured in units of pressure in step with a unit of surface vicinity ( P = F / A). In bodily technological know-how, the image for strain is p and the SI unit for measuring stress is the pascal (image: Pa). One pascal is the pressure of one Newton consistent with a square meter appearing perpendicular on a floor.

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Complete Question:

During forced exhalation, such as when blowing up a balloon, the diaphragm and chest muscles create a pressure of 60.0 mm Hg between the lungs and chest wall. What force in newtons does this pressure create on the 600 cm2 surface area of the diaphragm?

This pressure exerts a 4.802 N force on the 600 cm2 surface area of the diaphragm.

The force delivered perpendicularly to an object's surface in accordance with the unit location across which that force is distributed is known as stress. The strain in relation to the ambient strain is known as gauge strain. There are several tools utilised for the particular strain. The amount of pressure applied to each site is referred to as strain.

The traditional unit of stress is the pascal (Pa). The kilopascal is the ideal measure for regular fuel pressures since a pascal is a relatively modest amount of tension (kPa). One thousand pascals is equivalent to one kilopascal. The atmosphere is another frequently used unit of pressure (atm). Pressure units along with a unit of surface proximity are widely used to quantify strain (P = F / A). In physical technology, the SI unit for measuring stress is the pascal, and the image for strain is p. (image: Pa). The pressure of one Newton equivalent to a square metre appearing perpendicular to the ground is one pascal.

Chest muscles create a pressure of 60.0 mm hg

P =60.0mm×133.3pa/1mm hg = 7998.

= 600/100² = 0.06

= 7998×0.06= 4.802N.

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Why does the graph slant upward in the first part but then level out? Drag the terms on the left to the appropriate blanks on the right to complete the sentences.

Answers

The graph slants upward in the first part and then levels out because it is showing the relationship between two variables that are not directly proportional.

What is graph in physics?

Graph in physics is a visual representation of a relationship between two or more physical quantities. It is used to show how these physical quantities are related and to make predictions about the physical system being studied. Graphs are an essential tool in physics, as they help to illustrate the relationships between physical variables in a clear and concise way. Graphs can also be used to calculate specific values, such as the speed of an object or the area of a circle.

As the independent variable (on the x-axis) increases, the dependent variable (on the y-axis) increases at a diminishing rate, until the point of saturation is reached and the graph levels out. The relationship between the two variables is referred to as an exponential relationship, where the dependent variable reaches its maximum value as the independent variable approaches infinity.

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When the speed of the electrons striking the anode is increased, the BLANK of the emitted X-rays increases.

frequency
density
wavelength

Answers

When the speed of electrons striking the anode increases, then the frequency of the emitted X rays increases.

What happens when the electrons hit the anode?

Electrons lose their kinetic energy when they reach the anode surface because they slow down dramatically. Heat or x-rays are created from kinetic energy. Individual atoms of the anode material engage in interactions with the electrons.

As electrons are accelerated from cathode towards the anode, more number of X rays are emitted. As the speed of the electrons increases,  thermionic emission increases resulting in more heat and number of X rays being released. frequency of the emitted x-rays increases?

Greater is the number of electrons striking the anode, then larger is the number of X−ray photons emitted.

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write an expression using the variables provided for the force applied by the student fs.

Answers

W = F. ds is the equation that results when a force F operates on a particle and the particle is moved by a displacement ds. F. ds. cos is equal to this dot product.

When there is force, there is work. There will always be a force, and that force will always work. The body will move slightly as a result of the imparted force. No force is applied if there is no displacement. Two requirements must be met in order for work to occur: a force must be applied. The force ought to result in some movement. Therefore, the formula for work is: work = product of force magnitude, displacement, and cosine of the angle formed by the vectors of force and displacement.

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A square copper loop,10.0 cm on a side,is located in a region of changing magnitude field.the direction of the magnetic field makes an angle 37° with the plane of the loop.the time changing field has the following time dependence , B(t) = 0.01T + (1.00×10^-3 T/s )t.find the induced emf in the copper loop for time t>0.

Answers

The induced emf in the copper loop is -79.86 mV.

What is induced emf?

The induced emf in the copper loop is given by the equation:

[tex]e = -(dΦ/dt) = - (d/dt)(BAcosθ)[/tex]

where Φ is the magnetic flux through the loop, B is the magnitude of the magnetic field, A is the area of the loop, and θ is the angle between the magnetic field and the plane of the loop.

Given that the side of the square loop is 10.0 cm, the area of the loop is ([tex]10.0 cm)^2 = 100 cm^2.[/tex]

[tex]B(t) = 0.01T + (1.00×10^-3 T/s )t ,[/tex]

Given that the direction of the magnetic field makes an angle 37° with the plane of the loop, so the angle θ=37°

Substituting the values we have:

[tex]e = - (100 cm^2)( d/dt)((0.01T + (1.00×10^-3 T/s )t)cos37°)e = - (100 cm^2)(1.00×10^-3 T/s) cos37°e = - (100 cm^2)(1.00×10^-3 T/s) * 0.7986e = - (79.86×10^-3 T/s)[/tex]

The induced emf in the copper loop is -79.86 mV.

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A certain circuit element is known to be a resistance, an inductance, or a capacitance.
Determine the type and value (in ohms, henrys, or farads) of the elemnt if the voltage and
current for the element are given by
a v(t) = 100 sin (200t +30°)V, i(t) = cos(200t +30°) A
b v(t) = 500 cos(100t + 50°)V, i(t) 2 cos(100% +50°)A
cv(t) = 100 cos(400t +30°)V, i(t) sin (100t+30°) A

Answers

To determine the type and value of the circuit element, we can use the relationship between voltage, current, and impedance for each type of element.

A. v(t) = 100 sin (200t +30°)V, i(t) = cos(200t +30°) A

The voltage and current are in phase, meaning that the circuit element is a resistance.

To determine the value of the resistance, we can use Ohm's law (V=IR).

100 = R * cos(200t + 30°)

R = 100/cos(200t + 30°) ohms

B. v(t) = 500 cos(100t + 50°)V, i(t) 2 cos(100% +50°)A

The voltage and current are 90 degrees out of phase, meaning that the circuit element is an inductance.

To determine the value of the inductance, we can use the relationship between voltage, current, and inductance (V = L di/dt).

500 = L * 2 * (-100sin(100t + 50°))

L = 250/100 = 2.5 henries

C. v(t) = 100 cos(400t +30°)V, i(t) = sin (400t+30°) A

The voltage and current are 90 degrees out of phase, meaning that the circuit element is a capacitance.

To determine the value of the capacitance, we can use the relationship between voltage, current, and capacitance (V = 1/C * ∫i(t) dt).

100 = 1/C * (-cos(400t+30°))

C = 100/-cos(400t+30°) farads

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If two city buses are traveling at 24 miles per hour and the buses are the same model and year but one bus has 30 passengers while the other bus has 12 passengers. Which is the best prediction?

Answers

If two city buses are traveling at 24 miles per hour and the buses are the same model and year but one bus has 30 passengers while the other bus has 12 passengers.  the best prediction is that the bus with 12 Passengers will cover those 24 miles with faster speed than the other.

What is Speed?

Speed means, the rate by which an object's location changes in any direction. The distance traveled in relation to the time it took to travel that distance is how speed is defined.

Miles:

mile, any of several distance measurements, such as the statute mile (5,280 ft) (1.609 km). It generally derived from the mille passus, or "thousand paces," of the Romans, which was equivalent to 5,000 Roman feet.

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Answer:

1. What does an object's kinetic energy depend on?

its mass and speed

2. Two city buses are traveling at 24 miles per hour. The buses are the same model and year. One bus has 30 passengers. The other bus has 12 passengers. Which is the best prediction?

The bus with 12 passengers will have less kinetic energy.

3. A softball player hits a ball at 78 miles per hour. Then she hits a ball at 80 miles per hour. Which is the best prediction?

The ball hit at 80 miles per hour will have more kinetic energy.

4. A hawk is chasing a sparrow. At the beginning of the chase, the hawk's kinetic energy is 5.1 Joules. At the end of the chase, the hawk doubles its speed. What is the best prediction for its kinetic energy at the end of the chase?

20.4 J

5. A student rolls two marbles down an inclined plane. One marble has a mass of 4.8 grams. The student calculates its kinetic energy to be 0.0035 Joules when it reaches the end of the plane. The second marble has a mass of 2.4 grams. What is the best prediction for its kinetic energy at the end of the plane?

0.00175 J

how much energy is stored in a 5.0-h inductor carrying 35 a?

Answers

The energy stored in a 5.0 henry inductor carrying 35 A is 3062.5 Joule.

What is inductance?

An electrical conductor's tendency to resist a change in the flow of current through it is known as inductance. The SI unit for inductance is Henry, and L is used to denote it.

Inductance of the inductor is: L = 5.0 Henry.

Current flowing through it is: I = 35 ampere.

Hence, the energy stored in it = 1/2 × L × I²

= 1/2 × 5.0 × 35² Joule

= 3062.5 Joule.

So, the energy stored in the inductor  is  3062.5 Joule.

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A pulley system has a mechanical advantage of 3, and an object weighing 9 Newtons must be lifted 15 meters. How much force
must be applied to lift the object?
Use the following equation to find the answer:
MA= F0/Fi
(1 point)
O 27 N
O 03 N
O 3 N
O 1.7 N

Answers

The amount of  force that must be applied to lift the object is 3 N.

option B is the correct answer.

How much force must be applied to lift the object?

The amount of force that must be applied to lift the load is calculated by applying formula of mechanical advantage.

The mechanical advantage of a simple machine is the ratio of load to effort applied to overcome the load. Also, it can be defined as the ratio of output force to input force, otherwise known as force ratio.

Mathematically, the formula for mechanical advantage is given as;

M.A = output force / input force

M.A = load / effort

The amount of  force that must be applied to lift the object is calculated as;

M.A = Fo / Fi

where;

Fo is the output force = loadFi is the input force = applied force

Fi = ( Fo ) / ( M.A )

Fi = ( 9 N ) / ( 3 )

Fi = 3 N

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A light bulb operating at 110 V draws 1.40 A of current. What is its resistance?

Answers

The value of resistance for given current and potential difference is 78.6 ohm.

The obstruction to current flow in an electrical circuit is measured by resistance. The Greek letter omega () represents the unit of measurement for resistance, known as ohms.

The ratio of the electric current flowing through it to the voltage applied is the definition of electrical resistance for a circuit component or device: Ohm's law, I = V/R, can be used to anticipate the behavior of the material if the resistance remains constant over a wide range of voltage.

V = 110

VI = 1.4 A

The voltage in this case is V, while the current is I.

Write the voltage expression based on Ohm's law, then rearrange the terms to arrive at the resistance expression, R. The value of R can then be calculated by substituting the necessary numbers.

V = I R

R = V / I

R = 110 / 1.40

R = 78.6 ohm

Here, 78.6 ohm is the measured value of resistance. As a result, choice B is accurate.

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A young boy of mass 45 kg is standing at rest on a stationary skateboard of mass 2.5 kg. He loses his balance and flies off the skateboard with a velocity of -2.8 m/s. What is the "recoil" velocity of the skateboard?

Answers

A young boy is standing at rest on a stationary skateboard. He loses his balance and flies off the skateboard, then the "recoil" velocity of the skateboard is calculated as 50.40 m/s.

What is recoil velocity?

When you fire bullet from gun, then gun experiences a force in the backward direction. Because of this force, gun attains velocity in the backward direction and this velocity is known as recoil velocity.

Given; v1, velocity of boy = -2.8 m/s ands m1, mass of boy = 45 kg and m2, mass of skateboard is 2.5 kg

Let v2 be recoil velocity of skateboard

As, m1u1+m2u2=m1v1+m2v2

u1=0; u2=0( given boy and skateboard at rest initially)

So,0=m1v1+m2v2

Hence, recoil velocity v2= -(m1/m2)v1.

= (- 45/2.5 )* -2.8

= 50.40 m/s

The "recoil" velocity of the skateboard is 50.40 m/s

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A sock stuck to the inside of the clothes dryer spins around the drum once every 2.0 s at a
distance of 0.50 m from the center of the drum.
What is it linear speed?

Answers

The sock's linear speed is 1.57 m/s.

What is  linear speed?

Linear speed is described as the measure of the concrete distance travelled by a moving object or the speed with which an object moves in the linear path is termed linear speed.

The sock spins once every 2.0 seconds, so its period is

T = 2.0 s

Therefore, the angular velocity of the sock is

angular velocity = 2π/ T

angular velocity = 3.14 rad/sec

The linear speed of the sock is given by

v = wr

where

w is the angular velocity

r = 0.50 m is the radius of the circular path of the sock

Substituting the values, we have that

v = wr = 3.14 x 0.50

v = 1.57 m/s.

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How would you describe the volume of the following object? the amount of water in a swimming pool O macroscopic O microscopic O submicroscopic O all of the above O none of the above

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Macroscopic is the right answer. The word "macroscopic" best describes the volume of water in a swimming pool. The "large picture" might be referred to as a macroscopic position.

High energy physics, which studies the physical systems, is another name for particle physics. Low energy physics is the study of physics at larger length scales, such as the macroscopic scale. The macroscopic scale is the length scale when things are large enough to be seen with the  eye without the use of optical magnifying devices. The polar opposite of microscopic, it. Pressure, volume, temperature, and other such things are typical instances of macroscopic characteristics. For instance, the only component of the structures of diamond and graphite is carbon.

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shows the interference pattern obtained in a double-slit experiment with light of wavelength 2λ.
Enter the letter(s) Indicating the fringe(s) In alphabetical order.

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The interference pattern obtained in a double-slit experiment with light of wavelength 2λ with an intensity ratio between the bright and dark fringes.

What happens to the double-slit pattern as the wavelength is increased?

Due to the dependence of the spacing between the slits on L, the spacings between various fringes get smaller as the distance between them gets bigger. The space between various fringes grows as the light's wavelength rises because this is a wavelength-dependent property.

What kind of pattern does a double-slit create?

The double-slit experiment shows that light is a wave and creates an interference pattern. The interference pattern is made up of alternate black and light lines; the light lines are known as fringes.

What is the interference pattern?

An interface establishes the communication barrier between two entities, in this case two pieces of software, as well as defining the signature actions of an entity.

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How fastmust a proton move so that its kinetic energy is 80% of its total energy? A) 0.92c B) 0.98c C) 0.87c D) 0.80c E) 0.020c

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The proton's speed will be 2.68 x 108 m/s if its overall kinetic energy is 80%.

What is kinetic energy?

The energy of motion, or kinetic energy, can be seen in the movement of an item or subatomic particle. Kinetic energy is present in every moving object and particle. Kinetic energy is present when something moves, such as a person walking, a baseball soaring through the air, a piece of food dropping from a table, or a charged particle in an electric field.

Kinetic energy of proton ,

K.E = ¹/₂mc²

c is the speed of light

m is the mass

Given, K.E2 is 80% of K.E1 i.e. 0.80K.E1

If K.E₁/c₁² = K.E₂/c₂²

c₂ = √(0.8K.E₁c₁²/K.E₁)

c₂ = √(0.8c₁²)

c₂ = c₁√(0.8)

c₂ = 3 x 10⁸ m/s x √(0.8)

c₂ = 2.68 x 10⁸ m/s

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Water flowing out of a 16.0 mm-diameter faucet fills a 1.00 L bottle in 15.0 s. At what distance below the faucet has the water stream narrowed to 10 mm diameter?

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The  3.12 cm distance below the faucet has the water stream narrowed to 10 mm diameter.

What is distance ?

Distance is the overall distance that an object actually travels along its course. The displacement of an object between two points is the smallest straight-line distance between those two points, measured from one position to the other. The metric system is used to measure both displacement and distance (m).

What is diameter ?

The centre of a figure or body is defined as a straight line. specifically: the length of a diameter, which is a line segment passing through the centre of a circle and ending on the circumference.

1 Liter converts to 1 X 10-3 m3, therefore the volume flow rate is

1 X 10-3/15 = 6.667 X 10-5 m3/s

That flow rate = Av so we can find v at the two different diameters

At 16 mm diameter, we get 6.667 X 10-5 = (π)(8 X 10-3)2(v)

v = .3317 m/s

At 10 mm diameter, we get 6.667 X 10-5 = (π)(5 X 10-3)2(v)

v = .8493 m/s

Finally apply vf2 = vo2 + 2ad

(.8493)2 = (.3317)2 + 2(9.8)(d)

d = .0312 m  which is 3.12 cm

Therefore,  3.12 cm distance below the faucet has the water stream narrowed to 10 mm diameter.

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Look at the screenshot and choose the correct statement from the options given.

Answers

Answer:

The force between two magnetic poles will increase as their separation is increased.

The pulmonary artery, which connects the heart to the lungs, is 8.5 cm long and has a pressure difference over this length of 450 Pa
Part A If the inside radius of the artery is 2.4 mm, what is the volume of blood that flows per second through the pulmonary artery? Express your answer using two significant figures
Part B If the radius of the artery is reduced by 10%, by what factor is the blood flow rate reduced? Assume that all other properties of the artery remain unchanged. Express your answer using two significant figures
(note: the answers need to be in cm^3/s)

Answers

The volume of blood that flows per second through the pulmonary artery  is  2.81 cm^3/s and the blood flow rate is reduced to 0.75.

A. To find the volume of blood that flows per second through the pulmonary artery, we need to use the formula for the volume flow rate of a fluid, which is:

Q = A × v

Where Q is the volume flow rate, A is the cross-sectional area of the artery, and v is the velocity of the blood flow.

We can find the cross-sectional area of the artery using the formula for the area of a circle:

A = πr²

Where r is the radius of the artery.

Substituting in the given values:

r = 2.4 mm = 0.0024 m

A = πr² = π×(0.0024 m)² = 1.13 × 10⁻⁶ m²

We are given that the pressure difference over the length of the pulmonary artery is 450 Pa, and Poiseuille's Law states that the flow rate of a fluid is directly proportional to the pressure difference, and inversely proportional to the viscosity of the fluid and the radius of the vessel, and directly proportional to the fourth power of the radius.

Q = (πr⁴Ρ)÷8ηL

Where η is the viscosity of the fluid and L is the length of the vessel.

Q = (π×(0.0024 m)⁴⁴⁵⁰ Pa)÷8η×8.510⁻² m

Q = 2.81 × 10⁻⁵ m³/s

Q=2.81×10⁻⁵ m³/s ×1000 cm³/m³ = 2.81 cm³/s

B. When the radius of the artery is reduced by 10%, the radius becomes 0.0024 m × 0.9 = 0.00216 m. The new cross-sectional area of the artery is A = π×(0.00216 m)² = 9.55 * 10⁻⁷ m²

Using Poiseuille's Law again we can find the new volume flow rate,

Q = (π×(0.00216 m)⁴⁴⁵⁰ Pa) ÷8η×8.510⁻² m

Q = 2.10 × 10⁻⁵ m³/s

Q=2.10×10⁻⁵ m³/s × 1000 cm³/m³ = 2.10 cm³/s

The new flow rate is 2.10 cm³/s / 2.81 cm³/s = 0.75

So the blood flow rate is reduced by a factor of 0.75 (or 75%) when the radius of the artery is reduced by 10%.

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How do I determine how much an objects weighs , their mass, and their acceleration and it’s direction from a free body diagram ?

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To determine the mass, weight, and acceleration of an object from a free body diagram, you need to use Newton's laws of motion.

State Newton's laws of motion?

The first law states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an external force. The second law states that the acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. The third law states that for every action, there is an equal and opposite reaction.

To calculate the mass of an object, you can use the equation F=ma, where F is the force applied to the object, m is the mass of the object, and a is the acceleration of the object. To calculate the weight, you can use the equation W=mg, where W is the weight of the object, m is the mass of the object, and g is the acceleration due to gravity. To calculate the acceleration of the object, you can use the equation a=F/m, where F is the net force acting on the object and m is the mass of the object. Finally, to determine the direction of the acceleration, you can look at the arrows in the free body diagram that represent the forces acting on the object.

Therefore, we determine how much an objects weighs , their mass, and their acceleration and it’s direction by using Newton's laws of motion.

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