Chapter 9

Question 1

Friction depends on…

Answer 1

1) type of surface in contact
2) force exerted be one surface on another

Question 2

Friction is independant of…

Answer 2

1) area of surface in contact
2) relative speed between the two surfaces

Question 3

What is the formula for speed?

Answer 3

distance travelled / time (m/s)

Question 4

What is the formula for pressure?

Answer 4

force / area = N / m square (Pa or N/m square)

Question 5

What is the formula for work done

Answer 5

force x distance travelled

Question 6

What is the formula of kinetic energy

Answer 6

½ x m x v square (½ x kg x m/s square) = J

Question 7

What is the formula of GPE

aka gravitational potential energy

Answer 7

mass x gravity x height = J

Question 8

What is the formula of power

forces

Answer 8

wd / t or E / t

Question 9

What is the Principle of Conservation Energy

Answer 9

• energy cannot be created or destroyed
• only converted from one form to another form
• total energy remains constant

Question 10

What is the formula for Acceleration?

Answer 10

a = (v-u) / t

v = final velocity, u = initial velocity, t = time

Question 11

What is the formula for force

Answer 11

F = ma

F = force, m= mass(kg) a = acceleration (m/s square)