Question

A body covers 12m in 2nd and 20m in 4th second. How much distance will it cover in 4sec after the 5th second

Answer 1

Answer:

s=u+1/2a(2n-1)

#12=u+1/2a*3 this is the first equation

#20=u+1/2a*7 this is the second equation

solving both the equations

we get 136m

Answer 2

Answer:

given,

S2nd=12m

u+a/2(2×2-1)=12

=2u+3a=12----(i)

S4th=20m

u+a/2(2×4-1)=20

=2u+7a=20----(ii)

(ii)-(i)=4a=8

a=2m/s^2

therefore(i)=u=3m/s

S5=3×5+1/2×2×5^2

=40m

S9=3×9+1/2×2×9^2

=108m

therefore the distance covered by the body in 4 sec after 5 sec is

S9-S5=108-40

=68m