The net force is 1350 kN
As per the question:
Mass of man, m = 60 kg
Initial speed of the car, v = 15 m/s
Final speed of the car, v' = 0 m/s
Distance covered by the person before coming to rest, d = 5 mm =
By using the third eqn of motion:
Thus the force on the person can be given by:
F = ma =
Try rubbing a plastic pen through your hair, and you'll find that you can pick up a tiny scrap of paper when the pen is about one centimeter above the paper. from this simple experiment you can estimate how much an atom in the paper is polarized by the pen! you will need to make several assumptions and approximations.
An accelerometer is a device that uses the extension of a spring to measure acceleration in terms of Earth's gravitational acceleration (g). What is the approximate acceleration if this accelerometer spring is extended just 0.43 centimeters?. . a) 0.24 g. b) 0.80 g. c) 2.00 g. d) 2.40 g
The first person to answer was correct
It takes 180 kj of work to accelerate a car from 21.0 m/s to 27.0 m/s. what is the car's mass?
F Penny's piston is wider than Pauly's, who is pushing with greater force?
How does a radio station know how many listeners?
A. Your friend strikes a gong across the room from you. How does the gong make a sound? How does the energy of the sound reach you? Why don't you feel a push of air when you hear the sound? Write three or four sentences to state your answers. b. Describe the amplitude and frequency of the sound wave for a low, soft note. Identify the characteristic of the sound that is connected to each wave property.
c. Write two or three sentences to define intensity and to state how intensity changes as the distance from the sound is decreased.
d. A sound is transmitted through equal lengths of aluminum and alcohol. In which material does sound travel faster? Write one or two sentences to explain your reasoning.
e. An ambulance with its siren wailing is moving away from an observer. Write two or three sentences to compare the pitch of the sound for the observer with the pitch for the ambulance driver. What is the term used to describe this phenomenon?
(a) Sound waves consists of rarefaction and compression. Sound needs a medium to travel. When a sound travels through a medium, the particles of the air vibrate. There will be compression where the density of air particle is more and rarefaction where there will be less density of air particles.
Sound is a form of energy. It transfers the energy from particle of air to another particle. In this way, a person able to hear the sound.
The loudness of the sound depends on the amplitude. Higher the amplitude, more will be loudness. Lower the amplitude, lesser will be loudness. The frequency of the sound depends on the pitch. The higher frequency correspondence to high pitch. The lower frequency correspondence to low pitch.
The intensity of the sound obeys the inverse square law. The intensity of the sound is inversely proportional to square of the distance. As the distance increases the intensity of the sound decreases.
Sound travels faster in the solid than liquid and gas. A sound travels faster in aluminium than alcohol.
An ambulance with its siren wailing is moving away from an observer. The difference in the sound of the siren is due to the phenomenon called Doppler effect. This phenomenon is observed when the source is moving with respect to an observer.
When an ambulance approaches then the siren sounds louder and more shrill. But there is a sudden change in the pitch when an ambulance overtakes an observer. There is an apparent increase in the frequency of the wave.
a) The gong elastically deflects and then pushes the molecules of air making sound. Then these molecules push other molecules along the direction of the sound. The energy is small and we can't feel it. However try stand in front of loud low frequency speaker, you will feel it without your ears.
b) Low soft noise: low frequency, low amplitude. frequency is responsible for making bass or high sounds, amplitude makes sound loud or silent.
c) Sound intensity is power per area. Increase distance - area of a spherical sound wave front will increase and intensity will decrease.
d) Speed of sound depends on stiffness and density of a medium,. Without any calculations I'd say that the speed of sound in alcohol is higher.
e) The Doppler effect. For ambulance driver the sound will be higher and louder than for observer cause wavelength will increase, frequency decrease outside the car.
What is true about the relationship between the kinetic energy of molecules in an object and the objects temperature? A. As the kinetic energy of molecules decreases the temperature increases
B. As the temperature increases the kinetic energy of the molecules decreases
C. The total kinetic energy of the molecules is not affected by a change in temperature
D. The kinetic energy always increases whether the temperature increases or decreases
As the temperature increases the kinetic energy of the molecules increases, if u add more heat you get more kinetic energy.
A neutral K meson at rest decays into two π mesons, which travel in opposite directions along the x axis with speeds of 0.828c. If instead the K meson were moving in the positive x direction with a velocity of 0.486c, what would be the velocities of the two π mesons?
The velocity of the two -meson are 0.574 in positive direction and - 0.9367c in the negative direction along X-axis
As per the question:
The speed of the -meson along x-axis, v' = 0.828c
The speed of the K-meson along positive x-axis, v'' = 0.486c
Now, to calculate the velocities of the two -meson:
Velocity of the first -meson, :
Velocity of the second -meson, :
To solve this problem, we need to use the following formula
In same direction, we have
Notice, that we just replaced each given value, and solve basic operations.
In different direction,
As you can observe, to solve this kind of problem, you just neet to consider the right sign of each velocity, when they are in the same direction, they must have the same sign, but when they are in opposite direction, they must have different signs.
Therefore, the answers are and
You sit at the outer rim of a Ferris Wheel that rotates 2 revolutions per minute (RPM). What would your rotational speed be if you were instead clinging to a position halfway from the center to the outer rim. Be sure to provide at least 3 to 4 complete content related sentences and show any work needed to support your answer
The rotational speed will be the same
When there is a circular motion involved (as in this case with the Ferris Wheel), the rotational speed is defined as the ratio between the angle covered and the time taken to cover that angle ():
Since all the points along a radius of the the Ferris Wheel rotates coherently, they cover the same angular distance in the same amount of time, so the rotational speed is always the same for every point of the Wheel. This means that if you change the distance by moving halfway from the centre, the rotational speed is still 2 revolutions per minutes, because a point halfway from the centre also covers 2 complete revolutions in a minute.