Question

When the speed of a car is u, the minimum distance
over which it can be stopped is s. If the speed becomes
nu, what will be the minimum distance over which it
can be stopped if retarding acceleration is same?
(a)s in (b) ns (c) sln Wurs
. Cointrincar has an
1​

Answer 1

Answer:

The minimum distance is : n²s unit.

Explanation:

As,

v²-u²=2as

                    As the car is stopped so the acceleration will be -a and final speed=0.

putting above values we get,

-u²=-2as        ;        s=u²/2a ----------eq. 1

Now initial speed is nu

As retarding acceleration will be same i.e. -a

-(nu)²=-2ax        (let the min. distance taken by car to stop=x)

rearranging we get,

x=n².u²/2a  

so x=n²s.   (∵u²/2a = s from eq.1)