Question

A motorcyclist starts from rest and reaches a speed of 16m/sec after travelling with uniform acceleration for 4sec. what is his acceleration.

Answer 1

The motorcyclist starts journey from rest. Hence the initial speed of the motorcyclist is zero.

• $\sf{u=0\ m\,s^{-1}}$

The motorcyclist attains a speed of $\sf{16\ m\,s^{-1}}$ after 4 seconds of journey.

• $\sf{v=16\ m\,s^{-1}}$

• $\sf{t=4\ s}$

Let $\sf{a}$ be the acceleration of the motorcyclist.

We have, the first equation of motion,

$\longrightarrow\sf{v=u+at}$

Hence the acceleration is,

$\longrightarrow\sf{a=\dfrac{v-u}{t}}$

$\longrightarrow\sf{a=\dfrac{16-0}{4}}$

$\longrightarrow\sf{a=\dfrac{16}{4}}$

$\longrightarrow\sf{\underline{\underline{a=4\ m\,s^{-2}}}}$

Hence the acceleration of the motorcyclist is $\bf{4\ m\,s^{-2}.}$

Answer 2

A motorcyclist starts from rest and reaches a speed of 6 m/s after travelling with uniform acceleration for 3 s. A motorcyclist starts from rest and reaches a speed of 6 m/s after travelling with uniform acceleration for 3 s.