Forces and Motion

Question 1

What equation links velocity, displacement and time?

Answer 1

displacement (m) = velocity (ms^-1) x time (s)

s = v x t

Question 2

What equation links acceleration, velocity and time?

Answer 2

acceleration (ms^-2) = change in velocity (ms^-1) ÷ time taken (s)

a = Δv ÷ t

Question 3

A ball is thrown upwards. After 2 seconds it is caught moving downwards at 10 ms^-1.

With what velocity was it thrown?

(acceleration due to gravity = -9.8ms^-2)

Answer 3

1. v = u + at
2. -10 = u + (-9.8 x 2)
3. -10 = u - 19.6
4. u = 9.6ms^-1

Question 4

How can you calculate distance travelled from a velocity-time graph?

Answer 4

The area under the graph for the is the distance travelled.

Question 5

What equation links force, mass and acceleration?

Answer 5

force (N) = mass (kg) x acceleration (ms^-2)

f = m x a