A train 400m long passes a pole in 20 seconds. What is the speed of the train?
- A70 km/hr
- B72 km/hr
- C68 km/hr
- D64 km/hr
Solution & Step-by-step Explanation
When a train passes a stationary pole, the distance covered is equal to the length of the train.
Distance=400m
Time=20seconds
Speed=
Time
Distance
=
20
400
=20m/s
To convert the speed from m/s to km/hr, multiply by
5
18
:
Speed=20×
5
18
=4×18=72km/hr
Distance=400m
Time=20seconds
Speed=
Time
Distance
=
20
400
=20m/s
To convert the speed from m/s to km/hr, multiply by
5
18
:
Speed=20×
5
18
=4×18=72km/hr