Question

a car starts from rest and accelerates uniformly from 10 s to attain a velocity of 20 m/s. If the mass of the car is 800 kg, then find the force exerted by the car.

Answer 1

Answer:

1600 N

Explanation:

According to the given question,

u = initial velocity = 0 m/s

v = final velocity = 20 m/s

t = time = 10 sec

m = mass = 800 kg

a = acceleration

And we are asked to find the force exerted by the car. But for that we have to know the acceleration as mass is already given.

We know,

• v = u+at

Putting the values we get,

• 20 = 0+ 10a

• 10a = 20

• a = 20/10

• a = 2 m/s^2

Thus acceleration of the car is 2 m/s^2.

Now, from Newton's 2nd law,

• F = ma

Where F is the force

Putting the values we get,

• F = 800×2

• F = 1600 N

So the force exerted by the car is 1600 N.