Question

What is the impulse of a 3 kg object that starts from rest and moves to 20 m/s?

Answer 1

The impulse on the object is 60Ns.

Step-by-step explanation:

Impulse is defined as the product of the force applied on an object and the time at which it acts. It is also the change in the momentum of a body.

F = m a

F = m(
`(v_(2) - v_(1) )/(t)`)

⇒ Ft = m(
`v_(2)` -
`v_(1)`)

where: F is the dorce on the object, t is the time at which it acts, m is the mass of the object,
`v_(1)` is its initialvelocity and
`v_(2)` is the final velocity of the object.

Therefore,

impulse = Ft = m(
`v_(2)` -
`v_(1)`)

From the question, m = 3kg,
`v_(1)` = 0m/s and
`v_(2)` = 20m/s.

So that,

Impulse = 3 (20 - 0)

= 3(20)

= 60Ns

The impulse on the object is 60Ns.