A 970 kg car starts from rest on a horizontal roadway and accelerates eastward

for 5 s when it reaches a speed of 25 m/s. What is the average force exerted on

the car during this time? (Hint: Find acceleration of the car, then use the equation

F=ma.)

Answer: 4850N

Explanation:

Mass of car = 970 kg

Time = 5 s

Speed = 25 m/s

Average force exerted on the car = ?

Recall that Force is the product of the mass of an object and the acceleration by which it moves

i. e Force = mass x acceleration

(Since, acceleration is the rate of change of velocity or speed per unit time)

i. e Acceleration = Speed / Time

Acc = 25m/s / 5s

Acc = 5m/s^2

Average force = mass x acceleration

Avg force = 970 kg x 5m/s^2

= 4850N

Thus, the average force exerted on the car is 4850 Newton