Chapter 5- Work, Energy and Power

Question 1

Energy

Answer 1

A measurement of the ability of something to do work

Question 2

Work

Answer 2

The energy transferred by a force onto the object

Work is when something is moved against an opposing force

Question 3

Smooth

Answer 3

There is no friction

Question 4

When pushed at an angle

Answer 4

W = Fxcos(theta)
F = force
x = distance
theta = angle to the surface

Question 5

Kinetic energy

Answer 5

Energy due to motion of an object with mass

Question 6

Gravitational potential energy

Answer 6

Energy of an object due to its position in a gravitational field

Question 7

Chemical energy

Answer 7

Energy contained within the chemical bonds between atoms

Question 8

Elastic potential energy

Answer 8

Energy stored in an object as a result of reversible change in its shape

Question 9

Electrical potential energy

Answer 9

Energy of electric charges due to their position within an electric field

Question 10

Nuclear energy

Answer 10

Energy within the nuclei of atoms

Question 11

Radiant (or electromagnetic energy)

Answer 11

Energy associated with all electromagnetic waves, stored within the oscillating magnetic and electric fields

Question 12

Sound energy

Answer 12

Energy of mechanical waves due to the movement of atoms

Question 13

Internal (heat or thermal) energy

Answer 13

The sum of the random potential and kinetic energies of atoms in a system

Question 14

Potential

Answer 14

Means that energy is stored

Question 15

If we ignore friction and air resistance

Answer 15

Change in kinetic energy = change in GPE

Question 16

Using change in kinetic energy = change in GPE

Answer 16

v = root(2gh)

Question 17

Units of power

Answer 17

Watt(W) or Js^-1

Question 18

Work done

Answer 18

The energy transferred to an object by a force moving the object in the direction of the force