Question

A body initially moving with a velocity of $5{\text{ms}}^{–1}$, attains a velocity of $25{\text{ms}}^{–1}$ in $5s$. The acceleration of the body is:
(Assume constant acceleration)

• A. $8{\text{ms}}^{-2}$
• B. $7{\text{ms}}^{-2}$
• C. $4{\text{ms}}^{-2}$
• D. $3{\text{ms}}^{-2}$

Answer 1

The correct option is C $4{\text{ms}}^{-2}$

Given,
$u=5{\text{ms}}^{-1},v=25{\text{ms}}^{-1},t=5\text{sec}$
$\because v=u+at$ (From $1^{st}$ equation of motion)
$\therefore a=\frac{v-u}{t}=\frac{25-5}{5}=\frac{20}{5}=4{\text{ms}}^{-2}$