Question

A car moving with a velocity of 10 m/s can be stopped by the
application of a constant force F in a distance of 20 m. If the
velocity of the car is 30 m/s it can be stopped by this force in:
a. 100 m
b. 120 m
c. 180 m
d. 160 m​

Answer 1

Answer:

The car can be stopped by this force in 180 m.

Explanation:

Given that,

velocity of car = 10 m/s

distance s = 20 m

Let the mass of the car be m.

Case (I).

Using equation of motion

Negative sign shows the retardation because the speed is decreasing.

For case (II),

Velocity v = 30 m/s

The force is same.

So, The acceleration will be same.

Using equation of motion again

Hence, The car can be stopped by this force in 180 m.

Answer 2

Answer:

(c) 180............................