Question

A bus is moving along a straight road with a uniform acceleration. It passes through two points A and B separated by a certain distance with velocity of $30$ kmph and $40$ kmph respectively.Velocity of the car exactly midway between A and B is

• A. 38.3 kmph
• B. 35.35 kmph
• C. 33.3 kmph
• D. None

Answer 1

Answer: (B)

35.35 kmph

$v=u+at$
$40=30+at$
$at=10$
$v^2=u^2+2as$
${40}^2={30}^2+2as$
$2as=700$

Now at midway $s^1=\frac{s}{2}$
$v^2=u^2+2a\frac{s}{2}$
$v^2={30}^2+\frac{700}{2}=900+350$
$v^2=1250$
$v=\sqrt{1250}=35.35kmph$