Question

a 0.002 kg coin, which has zero potential energy at rest, is dropped into a 10.0 m well. after the coin comes to a stop in the mud, what is its potential energy? 0.020 j -0.196 j 0.000 j 0.196 j

Explanation:

Step1: Recall potential - energy formula

The formula for gravitational potential energy is $U = mgh$, where $m$ is the mass, $g$ is the acceleration due to gravity ($g= 9.8\ m/s^{2}$), and $h$ is the height relative to the zero - potential level. Here, the zero - potential level is the initial position of the coin, and the coin moves downwards, so $h=- 10.0\ m$ (negative because the final position is below the initial position), $m = 0.002\ kg$, and $g = 9.8\ m/s^{2}$.

Step2: Calculate potential energy

Substitute the values into the formula: $U=mgh=(0.002\ kg)\times(9.8\ m/s^{2})\times(-10.0\ m)=- 0.196\ J$.

Answer:

B. -0.196 J