Questions: A 2.80 kg mass is dropped from a height of 4.50 m. What is the potential energy of the mass when it reaches the ground? PE=[?] J

Solution Steps

The potential energy ($PE$) of an object at a height ($h$) is given by the formula: $$PE = mgh$$ where:

• $m$ is the mass of the object,
• $g$ is the acceleration due to gravity ($9.8 \, \text{m/s}^2$),
• $h$ is the height from which the object is dropped.

Given:

• $m = 2.80 \, \text{kg}$,
• $h = 4.50 \, \text{m}$,
• $g = 9.8 \, \text{m/s}^2$.

Substitute these values into the formula: $$PE = 2.80 \times 9.8 \times 4.50$$

Perform the multiplication: $$PE = 2.80 \times 9.8 \times 4.50 = 123.48 \, \text{J}$$

Thus, the potential energy of the mass when it reaches the ground is $123.48 \, \text{J}$.

Final Answer