2.7 Conservation Of Energy

Question 1

What is the Principle of Conservation of Energy?

Answer 1

Energy cannot be created or destroyed. Energy is always conserved (it can be changed from one form into another)

Question 2

What is the unit of energy?

Answer 2

Joules (J)

Question 3

What are examples of energy transformations?

Answer 3

Light bulb: electrical energy—-> light energy (and heat energy)
Hoover: electrical energy—-> kinetic energy (and sound energy)

Question 4

What is the symbol for work done?

Answer 4

Ew

Question 5

What is the equation involving work done, force and displacement?

Answer 5

Work done= force x displacement

Ew= F x s

Question 6

What is gravitational potential energy?

Answer 6

The work done against gravity.

Question 7

What is the symbol for potential energy?

Answer 7

Ep

Question 8

What is the equation involving potential energy, mass, gravitational field strength and height?

Answer 8

Potential energy= mass x gravitational field strength x height
Ep= m x g x h

Question 9

What kind of energy does a moving object have?

Answer 9

Kinetic energy

Question 10

What is the symbol for kinetic energy?

Answer 10

Ek

Question 11

What is the equation involving kinetic energy, mass and velocity?

Answer 11

Ek= 1/2 x m x v squared