Calculating the potential energy (PE) of a falling object is a fairly simple process involving only a few numbers and a bit of arithmetic. To figure out the change in potential energy, you do the calculation twice: once for the starting position, once for the final position, then you subtract the second energy result from the first.
- Measuring stick
Measure the initial height and mass of the object. Record your values.
Calculate your object's initial potential energy using the following equation:
Use the height and mass you measured along with 9.8 m/s2 as the constant for gravity. The result will be your initial potential energy.
Determine the object's final height and mass. Record your values.
Compute the object's final potential energy. Use the same equation as before while still using 9.8m/s2 as the constant for gravity. But, this time use your object's final height and mass. This number will be your final potential energy.
Use the following equation to determine change in potential energy:
The final number is your change in potential energy.
Things You'll Need
- Do not round your values. Be exact with your measurements. In some cases, even the smallest miscalculation may give you the wrong answer.
- Remember to keep your units constant. Do not measure your initial height in feet and then measure your final height in meters. This will not give you the correct answer.
About the Author
Pranav Reddy started writing professionally in 2010. He has written automotive, society, culture and science articles for various websites. Reddy is pursuing his Bachelor of Science in molecular biology and neuroscience at the University of Colorado, Boulder.