The mass of earth is `6 xx 10^(24)kg` and radius is 6400 km. How much amount of work will be done to make the duration of day its 20 hours rather than 24 hours.

Explanation

To solve the problem of how much work will be done to change the duration of the day from 24 hours to 20 hours, we will follow these steps:

### Step 1: Gather Given Data
- Mass of the Earth, \( M = 6 \times 10^{24} \) kg
- Radius of the Earth, \( R = 6400 \) km \( = 6400 \times 10^3 \) m \( = 6.4 \times 10^6 \) m
- Initial time period (24 hours) \( T_1 = 24 \) hours
- Final time period (20 hours) \( T_2 = 20 \) hours

...