Answer:
(a) 102 cm/s
(b) 0.490 cm²
Explanation:
(a) Use Bernoulli equation.
P₁ + ½ ρ v₁² + ρgh₁ = P₂ + ½ ρ v₂² + ρgh₂
0 + ½ ρ v₁² + ρgh₁ = 0 + ½ ρ v₂² + 0
½ ρ v₁² + ρgh₁ = ½ ρ v₂²
½ v₁² + gh₁ = ½ v₂²
½ (25.0 cm/s)² + (980 cm/s²) (5.00 cm) = ½ v²
v = 102 cm/s
(b) The flow rate is constant.
v₁ A₁ = v₂ A₂
(25.0 cm/s) (2.00 cm²) = (102 cm/s) A
A = 0.490 cm²
Consider a particle of mass m which can move freely along the x axis from -a/2 to a/2, but which is strictly prohibited from being found outside this region. The wave function of the particle within the allowed region is
Answer:
φ = B sin (2π n/a x)
Explanation:
In quantum mechanics when a particle moves freely it implies that the potential is zero (V = 0), so its wave function is
φ = A cos kx + B sin kx
we must place the boundary conditions to determine the value of the constants A and B.
In our case we are told that the particle cannot be outside the boundary given by x = ± a / 2
therefore we must make the cosine part zero, for this the constant A = 0, the wave function remains
φ = B sin kx
the wave vector is
k = 2π /λ
now let's adjust the period, in the border fi = 0 therefore the sine function must be zero
φ (a /2) = 0
0 = A sin (2π/λ a/2)
therefore the sine argument is
2π /λ a/2 = n π
λ= a / n
we substitute
φ = B sin (2π n/a x)
1. Which statement is true of culture?
O Culture do not change or evolve
O Culture refers to the degree in which resources are used to address for problems.
O Culture has little affect on a persons life
Food can reflect culture
how far will a brick starting from rest fall freely in 3.0 seconds?
Answer: It will be about 44.1m
Explanation:
first correct answer gets brainliest
Answer:
electrical energy transforming into sound energy in speaker
Answer:
the first one. Electrical energy transforming into sound energy in a speaker
50 POINTS!!! PLEASE!!!!!! Pls help me with this been stuck on it in like FOREVER!! PLSS.
Answer:
it will move in 356.5g in diagonal direction(resultant or between the both direction)
Explanation:
285+428/2=356.5g
Hope u like it
PLZ MARK ME AS BRAINLIEST
2 Why
Force is needed
Answer:
A force can cause an object to accelerate, slow down, remain in place, or change shape. The unit of measure for force is the newton which is abbreviated as "N". One newton is the force needed to accelerate one gram of mass by one centimeter per second squared. Other units of force include the dyne and the pound-force.
Help plz!:( it’s for physics but it has like math !!
(SHOW ALL WORK)
1) A 30-kg object is accelerated at a rate of 3m/s2. how much force does the object have?
2)A ball is thrown w/ a force of 50N and travels 4m. how much work is done to the ball?
3) Joey pushes on a door that is stuck with 400 N of force but is unable to move it. How much work has he done?
4) A toy car does 300j of work in 15 sec. how much power did the car use?
5)A 60w light bulb burns for 2 min. how much work was done?
6) how much power is used if it takes Frank (a 450 N boy) 3 sec to run 2 meters?
Answer:
1. 90N
2. 200N
3. 400N
4.20w
5.7200N
Explanation:
1.F=ma
30 * 3 = 90
2.W=FD
50 * 4=200
4. P=W/t
300/15=20
5.W= Pt. 2minutes = 120sec
60*120 = 7200
which two types of information are found in an elements box in the periodic table
Answer:
Each box represents an element and contains its atomic number, symbol, average atomic mass, and (sometimes) name.
Explanation:
Answer:
An element's period and group
The speed of a car is decreasing from 35 m/s to 15 m/s in 4s
A child and sled with a combined mass of 53.9 kg slide down a frictionless slope. If the sled starts from rest and has a speed of 5.71 m/s at the bottom, what is the height of the hill
Answer:
1.66m
Explanation:
Using the conservation law
PE = KE
mgh = 1/2mv²
gh = V²/2
g is the acceleration due to gravity = 9.81m/s²
h is the height of the hill
V is the velocity = 5.71m/s
Substitute
9.81h = 5.71²/2
Cross multiply
2×9.81h = 5.71²
19.62h = 32.6041
h = 32.6041/19.62
h = 1.66m
Hence the height of the hill is 1.66m
plzzz helppp
You are pushing a box North in the hallway, at 20n, and a friend gets in front of the box and goes in the opposite direction, at 30n. What direction is the box going at? How much force does the box have going in that direction?
Answer:
the box is going south at 10n
Explanation:
A cup of hot coffee initially at 95 degrees C cools to 80 degrees C in 5 min while sitting in a room of temperature 21 degrees C. Using Newton's law of cooling, determine when the temperature of the coffee will be a nice 50 degrees C.
Answer:
When the temperature of the coffee is 50 °C, the time will be 20.68 mins
Explanation:
Given;
The initial temperature of the coffee T₀ = 95 °C
The temperature of the room = 21°C
Let T be the temperature at time of cooling t in mins
According to Newton's law of cooling;
[tex]\frac{dT}{dt} \alpha (T-21)\\\\\frac{dT}{dt} = k (T-21)\\\\\frac{dT}{T-21} = kdt\\\\\int\limits {\frac{dT}{T-21}} = \int\limits kdt\\\\Log(T-21) =kt + Logc \\\\Log (\frac{T-21}{c} ) = kt\\\\T -21 = ce^{kt}\\\\At \ t = 0, T = 95\\\\95-21 = ce^0\\\\74 = c\\\\New, equation: T -21 = 74e^{kt}\\\\Again; when \ t= 5\ min, T = 80\\\\80 -21 = 74e^{5k}\\\\59 = 74e^{5k}\\\\e^{5k} = \frac{59}{74}\\\\ 5k = ln(\frac{59}{74})\\\\5k = -0.2265\\\\k = -0.0453[/tex]
When the temperature is 50 °C, the time t in min is calculated as;
[tex]T -21 = 74e^{-0.0453t}\\\\50 -21 = 74e^{-0.0453t}\\\\29 = 74e^{-0.0453t}\\\\\frac{29}{74} = e^{-0.0453t}\\\\0.39189 = e^{-0.0453t}\\\\ln(0.39189 ) = {-0.0453t}\\\\-0.93677 = {-0.0453t}\\\\t = \frac{-0.93677}{-0.0453}\\\\ t = 20.68 \ mins[/tex]
Therefore, when the temperature of the coffee is 50 °C, the time will be 20.68 mins
In 10 minutes the hot coffee will attain the temperature of 50 degrees Celsius.
Initially the hot cup of coffee at the temperature of 95 degrees Celsius but after 5 minutes its temperature decreases from 95 to 85 degrees Celsius which is 15 degrees Celsius decrease so in other 5 minutes, the temperature decreases to 65 degrees Celsius.
Again after 5 minutes the temperature will further decrease finally the cup of coffee attain the temperature of 50 degrees Celsius so we can conclude that in 10 minutes the hot coffee will gain the 50 degrees Celsius temperature.
Learn more: https://brainly.com/question/18402982
A charged isolated metal sphere of diameter 12 cm has a potential of 9200 V relative to V = 0 at infinity. Calculate the energy density in the electric field near the surface of the sphere.
Answer:
0.1 J/m³
Explanation:
We know that
V = k Q / R
We also know that
E = k Q / R²
Joining the two equations together, we have
E = V / R
To solve the question proper, we'd be using the formula
u = 1/2 E• E², substitute for E, we have
u = 1/2 E• (V/R)²
u = 1/2 * 8.85*10^-12 * (9000 / 0.06)²
u = 1/2 * 8.85*10^-12 * 150000²
u = 1/2 * 8.85*10^-12 * 2.25*10^10
u = 1/2 * 0.199125
u = 0.0996
u = 0.1 J/m³
The energy density is 0.1 J/m³
whats a difference between a objects kinetic energy and potential energy
Answer:
A object having kinetic energy is in motion state.And the object whi posses potential energy i s in state of podition.
Answer:
Objects are relative to other moving and stationary objects.
Kinetic energy can be transferred from one moving object to another.
Potential energy is stored energy in an object.
2. Which blood cells help in clotting of the blood
Answer:
Platelets
Explanation:
Platelets are tiny blood cells that help your body form clots to stop bleeding. If one of your blood vessels gets damaged, it sends out signals to the platelets. The platelets then rush to the site of damage and form a clot to stop the bleeding.
Answer:
[tex]\boxed {\tt Platelets}[/tex]
Explanation:
There are three main types of blood cells:
Red blood cells: transports oxygen to cells and carbon dioxide to lungsWhite blood cells: protects the body against disease Platelets: help clot blood and stop bleedingWe are looking for which blood cell helps clot the blood. From the list above, we can see the best answer is platelets.
I WILL MARK YOU AS BRAINLIEST IF RIGHT
What is the magnitude of the net force acting on this object? And what direction?
Answer:
The magnitude of the net force acting on an object is equal to the mass. and the direction is in 20N
Explanation:
what happens to the temperature of water as time elapses? IF YOU ANSWER IT I WILL MARK YOU A BRAINLEST ANSWER
Answer:
I think it will get colder
Explanation:
Answer:
The water molecules go faster as it gets colder they go slower
Explanation:
trust me thats the answer
21. A toy car starts from rest and begins to accelerate at 11.0 m/s2. What is the toy
car's final velocity after 6.0 seconds?
Answer:
Explanation:
Given parameters:
Initial velocity = 0
Acceleration = 11m/s²
Time = 6s
Unknown:
Final velocity = ?
Solution:
From the given parameters, we use one of the appropriate equations of motion to solve this problem.
V = U + at
V is the final velocity
U is the initial velocity
a is the acceleration due to gravity
t is the time taken
Input the parameters and solve;
V = 0 + 11 x6
V = 66m/s
The final velocity is 66m/s
A curve that has a radius of is banked at an angle of . If a -kg car navigates the curve at without skidding, what is the minimum coefficient of static friction between the pavement and the tires
Answer:
0.65
Explanation:
For whatever reasons, the parameters are not giving. So, I will assume by myself to make the calculations easier. You can substitute whatever it is to it from your question.
Given that
Radius of the road, r = 63 m
Speed of the car, v = 20 m/s
The relationship between a car that is passing through a curve and it's frictional force is said to be
U(s) * g = v²/r
In the formula above,
U(s) = coefficient of static friction
g = acceleration due to gravity, 9.8 m/s²
v = velocity of the car
r = radius of the road
Now when we substitute the earlier stated values, we have
U(s) * 9.8 = 20² / 63
U(s) * 9.8 = 400 / 63
U(s) * 9.8 = 6.35
U(s) = 6.35 / 9.8
U(s) = 0.65
Thus, our coefficient of static friction, based on the stated values is 0.65
Can someone please help me with this following question, If you could visit Pangaea what animals would you find
A). Penguins
B). Mammals
C). Dinosaurs
D). Eagles
Answer:
C). Dinosaurs
Explanation:
As the ball falls, how will the kinetic energy change? How will the gravitational potential energy change? How will the mechanical energy change?
Answer:
the Kinetic energy of the ball also increases.
the potential energy of the ball also increases.
mechanical energy of ball remains same.
Explanation:
KINETIC ENERGY:
The kinetic energy of the object depends upon the velocity of the object. As the formula suggests:
K.E = (1/2)mv²
As, the ball is falling down, it accelerates with a value equal to acceleration due to gravity. Thus, the speed increases as the ball falls.
Therefore, the Kinetic energy of the ball also increases.
POTENTIAL ENERGY:
Th potential energy of an object depends upon its height. As, the formula suggests:
P.E = mgh
As, the ball falls, its height decreases.
Therefore, the potential energy of the ball also increases.
MECHANICAL ENERGY:
Mechanical energy is the sum of kinetic energy and potential energy. According to law of conservation of energy, the total energy of the system always remains constant. It may change the forms but the total energy remains same. Thus, in this case potential energy is converted to kinetic energy.
Therefore, mechanical energy of ball remains same.
A 30.0-kgkg box is being pulled across a carpeted floor by a horizontal force of 230 NN , against a friction force of 210 NN . What is the acceleration of the box?
Answer:
The acceleration of the box is 0.67 m/s²
Explanation:
Given that,
Mass of box = 30.0 kg
Horizontal force = 230 N
Friction force = 210 N
We need to calculate the acceleration of the box
Using balance equation
[tex]F-f_{k}=ma[/tex]
[tex]a=\dfrac{F-f_{k}}{m}[/tex]
Where, F = horizontal force
[tex]f_{k}[/tex] =frictional force
m= mass of box
a = acceleration
Put the value into the formula
[tex]a=\dfrac{230-210}{30}[/tex]
[tex]a=0.67\ m/s^2[/tex]
Hence, The acceleration of the box is 0.67 m/s²
A car takes 8 s to increase its velocity from 10 m/s to
30 m/s. What is its average acceration?
Answer:
Average acceleration is 2.5 m/s^2.
Explanation:
Average acceleration can be found by dividing the change in speed by the change in time.
We know that the initial velocity=10m/s, the final velocity=30m/s and time elapsed is t=8s.
a= (Final velocity-Initial Velocty)/t
a=(30-10)/8=20/8=2.5 m/s^2
g (a) Calculate the block's final speed when it reaches the bottom of the frictionless inline. Keep 2 decimal places.
Answer:
Explanation:
The question is incomplete. Here is the complete question with attachment below.
In the above figure on the LEFT side, a block (mass = 2.8 kg) starts from rest at the top of a frictionless inline and slides to the bottom. The height of the incline is h=6.5 m, angle
I need to write 200 words about: boys are most influenced by their fathers and girls are most influenced by their mothers. Do you agree or disagree?
Answer:
I agree
Explanation:
I agree because most of the times girls pass more time with their mom since they hace more things in common, it’s the same with the boys.
Pleeeease Help!!
How did the parallel circuit respond differently to these changes than a series circuit?
Adding Bulbs: __________
Removing Bulbs: ________
Answer:
adding bulbs:bulbs will glow in parallel circuit.
but the brightness of each bulb differs in series circuit.
removing bulbs:if u remove a bulb from parallel circuit,the other bulbs continue glowing in the same brightness
but if u remove a bulb in series circuit,the brightness of each bulb increases.
Answer:
The person above is correct.
Explanation:
In a parallel sequence, the light bulbs have electrons that flow equally. Though, in a series circuit, it's mainly connected to one wire, and the electrons get weaker.
A metal ball sits motionless on a flat surface. Which of these would make the ball move?
A. The force of gravity becomes less.
B. The force of gravity becomes greater.
C. Two equal horizontal opposing forces act upon the ball.
D. Two unequal horizontal opposing forces act upon the ball.
Answer:
D
Explanation:
Unbalanced forces move stuff. Gravity would only increase/decrease movement if the object was already in motion.
Answer:
b
Explanation:
What cause objects to move? In three to five sentences .
Answer:
Gravity can affect the motion of objects as the force pulls objects closer to earth. Kinetic energy also causes movement in objects as that is energy in motion coming from stored energy known as (potential energy). With almost most importantly is needed is a force as without a force acting upon an objects is moving will continue to move and an object at rest will remain at rest as a gravitational pull or kinetic and potential energy for example are forces.
Explanation:
Have a great day :)
Determine the Northward and the Eastward components of a 75 m long displacement vector which points in a direction of 27^o E of N.
Answer:
Eastward = 34.05m
Northward = 66.8m
Explanation:
First, let's define our coordinate axis.
I will choose the North as the positive y-axis and the East as the positive x-axis.
Now we will work with polar coordinates, r and θ and remember that if we want to recover the rectangular coordinates, we need to compute:
x = r*cos(θ)
y = r*sin(θ)
(remember that θ is measured counterclockwise from the positive x-axis)
Now we have:
"... 75 m long displacement vector..."
r = 75m
"...points in a direction of 27° E of N..."
This means that the measure is from the positive y-axis, clockwise (so this is not equivalent to θ).
Now, remember that the angle between the positive y-axis and the positive x-axis is 90°.
Then we will have that θ is the complementary angle to 27°, or:
θ = 90° - 27° = 63°
Now we have θ and r, then we can calculate the rectangular components:
x = 75m*cos(63°) = 34.05m (this is the Eastward component)
y = 75m*sin(63°) = 66.8m (this is the Northward component)
An empty 50-g bowl rests on a scale that measures force (in newtons). Water is then poured into the scale from a height of 0.50 m and rate of 10 mL/s. Assuming that the water does not splash as it comes to rest, calculate the reading on the scale at t = 5.0 s
Answer:
1 Newton
Explanation:
Mass of bowl (Mb) = 50 g = 0.05 kg
Initial Velocity (Vo) = 10 mL/s = 10g/s
time (t) = 5.0s
Mass of water (Mw) = 10 g/s * 5s = 50 g = 0.05 kg
*Vob = initial velocity of bowl
*Vow = initial velocity of water
*Vf = final velocity
*g = gravity = 9.8
Conservation of momentum [Inelastic Collision]:
(m1)(Vo1) + (m2)(Vo2) = (M1+M2)Vf(Mw)(Vow) + (Mb)(Vob) = (Mw+Mb)Vf(50g)(10g/s) + (50g)(0) = (50g + 50g)(Vf)Vf = 500/100 = 5g/s = 0.005kg/sImpulse-Momentum Theorem:
Δp = mΔvScale Reading:
Δp + Mw(g) + Mb(g)= (0.05kg + 0.05kg)*(0.05kg/s) + (0.05kg*9.8) +(0.05kg*9.8)= 0.9805 = 1 Newton