Question

A ball of mass 0.35 kg hangs straight down on a string of length 13 cm. It is then swung upward, keeping the string taut, until the string makes an angle of 70° with respect to the vertical. Find the change in the gravitational potential energy of the Earth-ball system.

Answer 1

Answer:

PE=0.29J

Explanation:

According to the description, there is a angle and in point swung upward of 70°

So,

$Y=13*10^{-2}*cos(70) \\Y=0.0444m$

Appling the equation of Potential Energy we have,

$PE=mgh\\PE=(0.35)(9.8)(0.13-0.0444)\\PE=0.29J$