Question

A bicycle moves with a constant velocity of $5km/h$ for $10$ minutes and then decelerates at the rate $1$ $km/h^2,$ till it stops. Find the total distance covered by the bicycle.

Answer 1

Given,

Initial velocity, $u=5Km/h$

Time, $t=10min=\frac{1}{6}h$

The bicycle is going with constant velocity, a = 0

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

$s=ut$

$s=5\times \frac{1}{6}$

$s=\frac{5}{6}Km..........\left(1\right)$

In case (2),

$u=5Km/h$

$v=0$

$a=1Km/h^2$

Using equation of motion as,

$v^2-u^2=2as$

$0-{\left(5\right)}^2=2(-1)s$

$s=\frac{25}{2}Km$

Total distance,

$=\frac{5}{6}+\frac{25}{2}$

$=13.33Km$

Total distance covered by bicycle is $13.33Km$.