This is called average speed.Its really simple
The middle or centre of the Earth is the core. However the middle of the layers from the surface to the centre of the Earth is known as mantle.
Answer:
L/2
Explanation:
Neglect any air or other resistant, for the ball can wrap its string around the bar, it must rotate a full circle around the bar. This means the ball should be able to swing to the top position where it's directly above the bar. By the law of energy conservation, this happens when the ball is at the same level as where it's previously released vertically. It means the swinging radius around the bar must be at least half of the string length.
So the distance d between the bar and the pivot should be at least L/2
Answer: 
Explanation:
Given
Distance putty has to travel is 3.5 m
The initial speed of putty is 9.50 m/s
Using equation of motion to determine the velocity of putty just before it hits ceiling
So, the velocity of putty just before hitting is
Answer:
It will be A. So since its 2 times more the kinetic energy. But then you have to square it 2^2 = 4
