Answer:
The change in momentum is 
Explanation:
From the question we are told that
The time taken for the stone to stop is 
The net force on the rock is 
The impulse of the rock can be mathematically represented as

Substituting values


Now impulse is defined as the rate at which momentum change
Hence the change in momentum
of the rock is equal to the impulse of the rock
So

Answer:
The net power needed to change the speed of the vehicle is 275,000 W
Explanation:
Given;
mass of the sport vehicle, m = 1600 kg
initial velocity of the vehicle, u = 15 m/s
final velocity of the vehicle, v = 40 m/s
time of motion, t = 4 s
The force needed to change the speed of the sport vehicle;

The net power needed to change the speed of the vehicle is calculated as;
![P_{net} = \frac{1}{2} F[u + v]\\\\P_{net} = \frac{1}{2} \times 10,000[15 + 40]\\\\P_{net} = 275,000 \ W](https://tex.z-dn.net/?f=P_%7Bnet%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20F%5Bu%20%2B%20v%5D%5C%5C%5C%5CP_%7Bnet%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%20%5Ctimes%2010%2C000%5B15%20%2B%2040%5D%5C%5C%5C%5CP_%7Bnet%7D%20%3D%20275%2C000%20%5C%20W)
5.972 × 10^24 kg
it is the weight of earth
hope it is helpful to you
Answer: The wave can flip upside down.
Reflection is the bending of a wave when it cannot pass through. For example, plain mirrors which are flat, a ray of light hits the mirror and is reflected from the mirror since it cannot pass through
When reflection occurs the speed and frequency of the wave does not change but the wave is flipped upside down.
The speed does not change because speed is affected by the change in medium the frequency also remains the same since the energy of the wave does not change.