Question

A bus starting from rest moves with a uniform acceleration of 0.1ms square for two minutes.Find a the speed acquired
b the distance travelled

Answer 1

First, we write all the known values:
a=0.1 m/s^2
u=0
t=2 minutes=120 seconds
To find speed, 
We apply the formula,
v=u+at
v=0+(0.1)(120)
v=12 m/s
For the distance travelled,
s=ut+1/2at^2
s=(0)(120) + 0.5(0.1)(120)(120)
s=(12)(60)
s=720m
Hence distance travelled is 720 metres

Answer 2

"The speed a is $12\quad { ms }^{ -1 }$

The distance b is $7.2\quad \times \quad 10^{ 2 }\quad { m }$

Given:

Initial speed of the bus, u = 0

Acceleration, ${ a }\quad =\quad 0.1\quad { ms }^{ -2 }$

Time taken, $t\quad =\quad 2\quad { minutes }\quad =\quad 2\quad \times \quad 60s\quad =\quad 120{ s }$

Speed acquired, v = ?

Distance travelled, s = ?

Solution:

$(a) { v }\quad =\quad { u }\quad +\quad { at }{ v }$

$=\quad 0\quad +\quad \left( 0.1\quad \times \quad 120 \right)$

${ v }\quad =\quad 12\quad { ms }^{ -1 }$

(b) According to the equation of motion:

$v^{ 2 }\quad =\quad u^{ 2 }\quad +\quad 2as$

$v^{ 2 }\quad -\quad u^{ 2 }\quad =\quad 2as$

Where, s is the distance covered by the bus

$144\quad =\quad 0.2{ s }(12)^{ 2 }\quad -\quad (0)^{ 2 }\quad =\quad 2(0.1)s$

$144\quad =\quad 0.2{ s }$

$s\quad =\quad \frac { 144 }{ 0.2 }$

$s\quad =\quad 720\quad { m }\quad =\quad 7.2\quad \times \quad 10^{ 2 }\quad { m }$"