Question

A body starting from rest with uniform acceleration travles 40 m in first 4 sec .The velocity of object after next 16 sec will be​​

Answer 1

Answer:

100m/s is the answer

Explanation:

1 st case:-

u =  0

s  =  40

t  =  4 s

s(4) = ut + 1/2 at^2

putting the given values in the eqn,

40 = 1/2 * a * 4^2         [u=0]

on solving we get,

a = 5

2 nd case:-

given in qs to find velocity after next 16 s which means velocity after 20 s from begining(that is 20 s after the body was at rest)

therefore, t = 20

u=0

a=5 (which we find  in the first case)

so   s(20) = ut + 1/2 at^2

applying the abv values in the eqn,

     s(20)  = 1/2 * 5 * 400

     s(20)=1000

qs is to find velocity in this case.

therefore we apply the eqn

  v^2 = u^2+2as

v^2=2*5*1000    [u=0 ]

    =10000  or 10^4

therefore ,v=10^2 or 100

hope it help u