Question

What is the net force on a 7.2-kg car that increases its speed from 8.0 m/s to 14.0 m/s over 5.3 seconds?

Answer 1

8.15

Step-by-step explanation:

From the formula, F = ma we can say:

F = 7.2× a

since a isn't given in the question and f is not also given, we find a.

so a = change in velocity with time

i.e a= V—v ÷ t

therefore, we can say

14.0-8.0 ÷ 5.3

that will give us

6/5.3 =1.132

go back to the formula and put in the parameters

therefore, F = ma gives

F = 7.2×1.132

Ans = 8.15N

Answer 2

Answer: 8.14 N

Explanation: To solve for F we use F=ma. First we solve for acceleration a=vf -vi/t

14m/s-8m/s /5.3 s = 1.13 m/s²

Substitute the value to find F.

F=7.2kg x 1.13 m/s² = 8.14 N