Question

An express train crosses a person standing on a platform in 20 seconds. The length of the train is 200m. Find its velocity in kmph.

Answer 1

Answer:

25/19 kmph

Explanation:

Answer 2

Given:-

• Time taken by a train to cross a person = 20 second.
• The length of the train displacement = 200m

To find:-

• Find the velocity of the train.

Solutions:-

• Let the velocity of the train be 'v' m/s.

We know that;

• The velocity of the train = Displacement/Time
• Displacement = 200m
• Time = 20 second

• V => D/T

=> 200/20

=> 10m/s

Change the velocity of the train in km/hr.

• 1 km = 1000m
• 1 hr = 60 × 60 = 3600sec

=> 10 × 3600/1000

=> 36 km/hr

• Velocity = 36km/hr

Hence, the velocity of train is 36km/hr.

Some Important:-

• Velocity = Displacement/Time
• Displacement = final position - initial position
• Time = taken to cover the distance.

• V = a_f - a_i/t = a/t

Here

• v = velocity which is m/s (meter per second)
• af = final position of X
• ai = initial position of X
• t = time taken by the object to move along the distance (s)
• a =change in position (final – initial) (m)