Question

The time required to stop a car of mass 800 kg, moving at a speed of 20 m/s over a distance of 25 m is (i)2 s (ii)2.5 s (iii)4s (iv)4.5 s

Answer 1

Answer:

(ii) 2.5 s

Explanation:

Given, u=0 ms

−1

,v=20 ms

−1

Mass of car =800 kg,s=25 m

We know that, distance covered,

s=(

2

u+v

)t

⇒25=(

2

0+20

)t

=

10

25

=2.5s.