A rock of mass 200kg is dropped from a height of 200m. What is its potential energy at: a) 0 seconds b) Just before hitting the ground?

Here's how to calculate the potential energy:

The formula for gravitational potential energy (GPE) is:

$$GPE = mgh$$

where:

• $m$ is the mass of the object
• $g$ is the acceleration due to gravity (approximately $9.8 \text{ m/s}^2$)
• $h$ is the height of the object above a reference point

Given:
Mass ($m$) = $200 \text{ kg}$
Initial height ($h_0$) = $200 \text{ m}$
Acceleration due to gravity ($g$) = $9.8 \text{ m/s}^2$