Answer:
Force is 432.94 N along the rebound direction of ball.
Explanation:
Force is rate of change of momentum.

Final momentum = 0.38 x -1.70 = -0.646 kgm/s
Initial momentum = 0.38 x 2.20 = 0.836 kgm/s
Change in momentum = -0.646 - 0.836 = -1.472 kgm/s
Time = 3.40 x 10⁻³ s

Force is 432.94 N along the rebound direction of ball.
Answer:
117.72kW
Explanation:
Given data
Mass m= 50kg
height x = 2m
time taken = 2 minutes= 129 seconds
let us find the work done
WD= force * distance
WD= mgx
WD= 50*9.81*2
WD= 981 Joules
Let us find the power
Power= work * time
Power= 981*120
Power= 117720
Power= 117.72 kW
Hence the power spent is 117.72kW
Answer:
Normal, Gravity, Friction, and Air Resistance.
Explanation:
When a moving car skid to stop and its wheels are locked across, then the following forces will be applied on the car:
<u>Normal force:</u> It will act counter to gravity that pushes an object against a surface and acts perpendicular to the contact surface.
<u>Gravity:</u> Gravity force acts in each and every object having mass and it can not be avoidable. So, the gravity force will also apply to the car and attract it to the earth's surface.
<u>Friction: </u>Friction is a force that acts opposite to the motion and stops or slows motion. Friction will be applied to the car that will oppose the motion of the car and stop it.
<u>Air resistance:</u> air resistance is defined as the forces exerted by air that acts opposite to the relative motion of an object. Air resistance will also be applied to the car when it will skid to stop as we are always surrounded by the air.
Hence, the correct answers are "Normal, Gravity, Friction, and Air Resistance."
In solids, particles or atom are very closely arranged compared to gasses. When these particles are arranged in such proximity, vibrations from sound are very easily transmitted from one particle to another in the solid. Hence, the sound vibrations can travel through the solid medium more quickly than through a gas medium.
Speed of sound also depends on its frequency and the wavelength.
A) 140 degrees
First of all, we need to find the angular velocity of the Ferris wheel. We know that its period is
T = 32 s
So the angular velocity is

Assuming the wheel is moving at constant angular velocity, we can now calculate the angular displacement with respect to the initial position:

and substituting t = 75 seconds, we find

In degrees, it is

So, the new position is 140 degrees from the initial position at the top.
B) 2.7 m/s
The tangential speed, v, of a point at the egde of the wheel is given by

where we have

r = d/2 = (27 m)/2=13.5 m is the radius of the wheel
Substituting into the equation, we find
