Question

3. A 500 kg car and a 1000 kg truck are both moving at 5 m/s.

a. What is the ratio of their momentum and why?

Answer 1

The ratio of momentum is 1:2 since the velocity is constant and mass is of ratio 1:2

Step-by-step explanation:

Given

mass of car
`m_(car)` = 500 kg

mass of truck
`m_(truck)` = 1000 kg

velocity of car = velocity of truck = v = 5 m/s

momentum of car
`p_(car)` = ?

momentum of truck
`p_(truck)` = ?

We know that the momentum is given by: p = mv , where m is mass and v is velocity.

momentum of car
`p_(car)` =
`m_(car)` x v = 500 x 5 = 2500 kg.m/s

momentum of truck
`p_(truck)` =
`m_(truck)` x v = 1000 x 5 = 5000 kg.m/s

The ratio of momentum =
`(p_(car))/(p_(truck))`

=
`(2500)/(5000)`

=
`(1)/(2)` = 1:2

Here we infer that the ratio is 1:2. This is because momentum value depends on mass and velocity of body. In given problem velocity is constant. Hence depends only on mass. The ratio of mass is 1:2 and so the ratio of momentum.