Question

(a) How much gravitational potential energy (relative to the ground on which it is built) is stored in an Egyptian pyramid, given its mass is about 9 ✕ 109 kg and its center of mass is 45.0 m above the surrounding ground? J(b) What is the ratio of this energy to the daily food intake of a person (1.2 ✕ 107 J)? :1

Answer 1

(a) 3.969 x 10¹² J

(b) 330750 : 1

Step-by-step explanation:

The gravitational potential energy can be calculated as

E = mgh

Where m is the mass, g is the gravity and h is the height.

Replacing m = 9 x 10⁹ kg, g = 9.8 m/s², and h = 45.0 m, we get:

E = (9 x 10⁹ kg)(9.8 m/s²)(45.0 m)

E = 3.969 x 10¹² J

Then, we can calculate the ratio by dividing this amount by 1.2 x 10⁷ J, so

`(3.969*10^(12))/(1.2*10^7)=330750`

Therefore, the ratio is 330750 : 1