volume_mute
What is the potential energy with reference to the table?
publish date: 2023/07/03 05:08:00 GMT+10
volume_muteSuppose that a 5-kg object rests on a table. You lift it up to the ceiling, which is 2 meters above the table. What is its potential energy with reference to the table?
PE = joules
Correct Answer
(1) 98
Explanation
Remember that 5 kg is the mass of the object and that we must find its weight since its weight is equal to the force we have to exert to lift it. newton's second law states that
F = ma
or in this case:
Weight = mg (where g is the acceleration of gravity)
Weight = 5 kg • (9.8 m/s2)
Weight = 49 newtons, since 1 kg (m/s2) is a newton
PE = weight • height
PE = 98 joules (or newton • meters)
Reference
Basic Physics: A Self-Teaching Guide