Energy Basics
What is the energy an object has because it is moving?
Kinetic Energy
A soccer ball rolls across a field. What type of energy does it have because of its motion?
Kinetic energy
A bicycle speeds up. Does its kinetic energy increase or decreas?
Increase
A book rests rests on a desktop. What is the GPE relative to the desktop?
0 J
What is stored energy called?
Potential energy
A book sits in a high shelf. What type of potential energy does it have relative to the floor?
Gravitational potential energy
You lift a backpack higher above the floor. Does its gravitational potential energy increase or decrease?
Increase
A 2 kg book is 3 m above the floor. What is the GPE relative to the floor?
60 J
What unit measures both kinetic and potential energy?
Joules (J)
What type of energy is stored in a stretched rubber band?
Elastic potential energy
Two balls have the same speed. Ball B is lighter than Ball A. Which has more kinetic energy?
Ball A
A 4 kg ball moves at 2 m/s. what is it it’s kinetic energy?
8 J
What 2 quantities determine an objects kinetic energy?
Mass and Speed
What type of potential energy is stored in food and batteries?
Chemical potential energy
Two identical books sit on different shelves. Which has more GPE relative to the floor.
The book on the higher shelf
An object has 300 J of kinetic energy and a speed of 5 m/s. What is the mass of the objec?
24 kg
What is the sum of a systems kinetic and potential energy called?
Mechanical energy
A bird flies above the ground. What two types of mechanical energy does it have relative to the ground?
Kinetic energy and gravitational potential energy
An objects speed doubles but its mass stays the same. What happens to its kinetic energy?
It becomes 4 times as great
What is the formula for both KE and GPE?
KE= 1/2 mv2
GPE= mgh