Practice Energy in Physics
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
The capacity to do work or cause change in a physical system, measured in joules.
The 'currency' that makes things happen. It's what you need to move, heat, or change anything.
Example 1
easyA 2 \text{ kg} ball is held 10 \text{ m} above the ground and then dropped. What is its total mechanical energy at the top? Use g = 9.8 \text{ m/s}^2.
Example 2
mediumA 1000 \text{ kg} car traveling at 20 \text{ m/s} brakes to a stop. How much energy is dissipated as heat?
Example 3
easyName the energy transformations when a ball is thrown upward and comes back down.
Example 4
mediumA 3 \text{ kg} rock at 15 \text{ m} above the ground is moving at 4 \text{ m/s}. What is its total mechanical energy? Use g = 10 \text{ m/s}^2.