The displacement of a particle is represented by following equation:
`s=3t^(3) +7t^(2) +5t +8`
where is in metre and in second the acceleration of particle at s is

Options

A. 18 `ms^(-2)`
B. 14 `ms^(-2)`
C. 32 `ms^(-2)`
D. zero

Answer

c

Explanation

Here `s=3t^(3)+7t^(2)+5t+8`
Differentiating it twice w.r.t,.t. we get
`(ds)/(dt)=9t^(2)+14t+5`
`(d^(2)s)/(dt^(2))=18t+14`
This putting t=1 and `(d^(2)s)/(dt^(2))=a`
a=(18+14)=32 `ms^(-2)`