A 58kg person walks down a flight of stairs. Use the ground as the reference level. Calculate the person’s gravitational potential energy at the top of the stairs, on the landing, and at ground level.

Answer 1

To calculate the gravitational potential energy at different levels for the 58kg person, we need to use the formula:

Gravitational Potential Energy (PE) = mass (m) x gravitational acceleration (g) x height (h)

Given:
Mass (m) = 58kg
Gravitational acceleration (g) = 9.8 m/s² (standard value on Earth)

1. At the top of the stairs:
As the person is at the top of the stairs, the height (h) is the maximum.
Let's assume the height of the stairs is 7 meters (this value is needed to make the calculations). You can replace it with the actual height if provided.
PE(top) = 58kg x 9.8 m/s² x 7m = 4004 Joules

2. On the landing:
Assuming there is no change in the height, the gravitational potential energy on the landing is the same as at the top.
PE(landing) = 4004 Joules

3. At ground level:
As the ground is the reference level, the height (h) is zero.
PE(ground level) = 58kg x 9.8 m/s² x 0m = 0 Joules

Therefore, the gravitational potential energy at different levels are:
1. Top of the stairs (maximum height): 4004 Joules
2. On the landing: 4004 Joules
3. Ground level (reference level): 0 Joules