Question

calculate the force required to stop a car weighing 1500 kg and moving at a velocity of 30m/s in 10 seconds ​

Answer 1

Given :-

• Mass of the car = 1500 kg

• Initial velocity of the car = 30 m/s

• Time taken = 10 sec

• Final velocity = 0 m/s

To find :-

• Force  applied

Solution :-

First we need to find the acceleration of the car .Assuming that the car will move with uniform acceleration let's apply the first equation of motion in order to find a

v = u + at

here ,

• v = final velocity

• u = initial velocity

• a = acceleration

• t= time

⟹ 0 = u + at

⟹ u = - at

⟹ a = - u /t

⟹ a = - 30 /10

⟹ a = -3 m/s²

Note : negative denotes retardation

Now let's find the force applied by using Newton's second law

⟹ F = ma

⟹ F = 1500 x -3

⟹ F = - 4500 N

⟹ |F| = 4500 N

The magnitude of force is 4500 N