Question

A train travels on a straight track passing signal a at 20 m/s.it accerate uniformly at 2m/s and reaches signal b,100m further from



a. at b velocity of the train is.?

Answer 1

Given:

Train travels on straight track and passes signal "a" at 20 m/s. It accelerates uniformly at 2 m/s² and reaches signal "b" located 100 metres away from signal "a".

To find:

Velocity of train at signal "b".

Calculation:

Initial velocity of train is 20 m/s measured at signal "a".

Since the acceleration of the train is constant we can apply the standard equations of kinematics to solve this problem.

Applying 3rd equation of kinematics:

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

$= > {v}^{2} = {(20)}^{2} + (2 \times 2 \times 100)$

$= > {v}^{2} = 400 + 400$

$= > {v}^{2} = 800$

$= > v = \sqrt{800}$

$= > v = 28.28 \: m {s}^{ - 1}$

So final answer is:

Velocity of Train at station A is 28.28 m/s.