Question

A bus starts from rest with a constant acceleration of $5m/s^2$. At the same time a car travelling with a constant velocity $50m/s$ over takes and passes the bus. How fast is the bus travelling when they side by side?

Answer 1

Formulae,

$ut+\frac{1}{2}a{t}^2=50t$

$0+\frac{1}{2}\times 5\times t^2=50t$

$t=50\times \frac{2}{5}=20s$

$v^2=u^2+2as$

$v^2=0+2\times 5\times (50\times 20)$

$v^2=10000$

$\therefore v=100m/s$