Choice - B is the correct one.
At the top of the arc, at one end of the swing:
-- it's not going to get any higher, so the potential energy is maximum
-- it stops moving for an instant, so the kinetic energy is zero
At the bottom of the arc, in the center of the swing:
-- it's not going to get any lower, so the potential energy is minimum
-- it's not going to move any faster, so the kinetic energy is maximum
Answer:7.67
Explanation:
Given
Weight of Cathy 
Force exerted by rope 
Mechanical advantage is the ratio of load by Pulling effort



Answer:

Explanation:
The acceleration due to gravity on the surface of the Earth is given by:

where
G is the gravitational constant
M is the mass of the Earth
R is the radius of the Earth
Here we want to find the new Earth radius R' for which the gravitational acceleration at the surface, g', would be 3 times the current value of g:

So we would have

Solving the equation for R', we find
