Question

A 1500kg car is at rest before it accelerates when the light turns green. If it covers 45.0 meters in 15.0 seconds, what is the net force applied to the car?

Answer 1

Answer:

300N

Explanation:

Given parameters:

Mass of car  = 1500kg

Initial velocity  = 0m/s

Distance covered  = 45m

Time  = 15s

Unknown:

Net force applied  = ?

Solution:

From Newton's second law:

  Force  = mass x acceleration

  Force  = mass x $\frac{v - u}{t}$  

v is the final velocity

u is the initial velocity

t is the time taken

    Final velocity  = $\frac{45}{15}$   =3m/s

 Force  = 1500 x $\frac{3 - 0}{15}$   = 300N