(a) Calculate the rotational kinetic energy of Earth on its axis. (b) What is the rotational kinetic energy of Earth in its orbit around the Sun?

Solution 23 PE

Step 1 of 4:

In this question, we need to find rotational kinetic energy of Earth on its axis

In part (b) we need to find the rotational kinetic energy of Earth around the Sun

Part (a)

Step 2 of 4:

The rotational kinetic energy is given by

Here

However, we have

for a sphere

Mass of earth,

Radius of earth,

Thus we can write rotational kinetic energy as

Substituting values we get

Thus we have rotational kinetic energy of Earth along its axis as

Part (b)