Answer:
Part i)
h = 5.44 m
Part ii)
h = 3.16 m
Explanation:
Part i)
Since the ball is rolling so its total kinetic energy in this case will convert into gravitational potential energy
So we have

here we know that for spherical shell and pure rolling conditions






Part b)
If ball is not rolling and just sliding over the hill then in that case



Answer: the waves travel in an horizontal direction while the strings vibrate in a vertical direction.
The initial kinetic energy of the car is

Then, the velocity of the car is decreased by half:

so, the new kinetic energy is

So, the new kinetic energy is 1/4 of the initial kinetic energy of the car. Numerically:
When the object slides across the rough surface some of its potential energy will be lost to friction.
<h3>Conservation of mechanical energy</h3>
The law of conservation of mechanical energy states that the total mechanical energy of an isolated system is always constant.
M.A = P.E + K.E
When the object slides across the rough surface, some of the potential energy of the object will be converted into kinetic energy while the remaining potential energy will be converted into thermal energy due to frictional force of the rough surface.
P.E = K.E + thermal energy
Learn more about conservation of energy here: brainly.com/question/166559