Question

What best describes an impulse acting on an object?

Answer 1

Answer:

D) the product of an object's mass and its change in velocity

Explanation:

The impulse is defined as:

$I = F . \Delta t$  (1)

Where I is the impulse, F is the force and t is the time whereby the force will be applied on the object.

By using Newton's second law, the impulse can be related with the mass and the change in velocity as a consequence of the acting force:

$F = ma$  (2)

Where F is the force, m is the mass and a is the acceleration.

The acceleration can be determined using the equations for a Uniformly Accelerated Rectilinear Motion:

$a = \frac{\Delta v}{\Delta t}$  (3)

Where $\Delta v$ is the change in velocity ($v_{2} - v_{1}$) and $\Delta t$ is the interval of time ($t_{2} - t_{1}$)

Remember that the acceleration is defined as the change in velocity in an interval of time.

By replacing equation (3) in equation (2) it is gotten:

$F = m\frac{\Delta v}{\Delta t}$

$F . \Delta t = m\Delta v$

$F . \Delta t = m(v_{2} - v_{1})$

But $F . \Delta t$ is the impulse according with equation (1), therefore:

$I = m(v_{2} - v_{1})$

So what best describes an impulse acting on an object is the product of an object's mass and its change in velocity.

Answer 2

Answer:

option (D)

Explanation:

If a large force acting on a body for a very small interval of time, it is called impulse.

Impulse is a vector quantity. its SI unit is kg m/s.

The formula of impulse is given by

Impulse = Force x Δ t = change in momentum.