Question

A body covers 4m in 3rd second and 12m in 5th second. If the motion is uniformly accelerated, how far will it travel in the next 3 seconds?

Answer 1

Explanation:

let initial velocity be U and acceleration be A

sn=U+1/2a(2n-1)

a/q

u+1/2a(2×3-1)=4___1

u+1/2a(2×5-1)=12__1

eqn.2---eqn.1

=1/2a(2×5-1)-1/2a(2×3-1)=8

4a=16

a=4 Ms-2

by 1.

u+1/2a×4×5=4

u= -6 Ms-1

total distance covered 8 s

-6×8+1/2a×4×(8)2

80m

distance covered by 15 s

= -6×5+1/2a×4×(5)

=20m

so distance coverd in next 3 seconds after 5th second will be

80-20=60m

hope this will be helpful