General Physics 1.6 Momentum

Question 1

Give the equation for momentum, including units

Answer 1

Momentum (kgm/s) = mass (kg) x velocity (m/s)

Question 2

The time taken for the change in momentum to occur is proportional to the…

Answer 2

Resultant force felt by the object.
(Newton’s second law: F=ma, where mass x acceleration is the rate of change of momentum)

Question 3

Give the equation linking resultant force and momentum

Answer 3

change in momentum (kg/s) = resultant force (N) x time (s)
mv - mu = Ft
Where…
m = mass (kg)
v = initial velocity (m/s)
t = time (s)
F = force (N)
u = finalvelocity (m/s)

Question 4

What is impulse?

Answer 4

The change in momentum of an object caused by a force acting on it for a length of time.

Question 5

What is the principle of conservation of momentum?

Answer 5

Momentum is always conserved in an explosion/collision, so there is no net change in momentum.
Momentum before = momentum after
(provided there are no external forces).