What is the net force on a 6.2-kg car that increases its speed from 6.2 m/s to 17.1 m/s over 4.0 seconds?

Answer 1

Hi Jessica,

This is a problem involving Newton's 2nd Law of Motion. When a net force acts on an object, it accelerates. The equation form of N2L is F = ma.. This is the equation you will be using.

You are given the mass as 6.2 kilograms.

You are not given the acceleration, but you can calculate it knowing that acceleration is equal to the change in velocity divided by the change in time. The change in velocity is 17.1 - 6.2 = 10.9 m/s. This change happens in 4.0 s. So, the acceleration is 10.9/4.0 = 2.7 m/s^2.

Now, we can substitute into the equation:

F=ma

F=(6.2)(2.7)

F=17 N (16.74 before rounding).

Hope this helps! :)

Answer 2

Force is mass times acceleration: F = ma

To get the acceleration, get the change in velocity and divide by the time.

For this problem:

change in velocity = 17.1 - 6.2. After subtracting, divide by 4 to get the acceleration. Then use F=ma