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

Its 1.73793151243 as a whole but if rounded it is 1.74
Answer:
The precise point is that gravitational energy is potential energy unless it makes something move, and then the energy is converted to kinetic energy, no work can be done. So a big rock at the top of a hill has no kinetic energy. Its only when it rolls down that work is done, and this can be converted to useful energy.
Explanation: