## Speed, Time and Distance

#### Speed, Time and Distance

1. A train is running with the speed of 45 km/hour. What is its speed in meter per second ?
1. 12.5
2. 13.5
3. 20.5
4. None of these

1. Speed of a train in kilometer per hour = 45
Speed in meter per second = ( 5/18 ) x Speed in kilometer per hour

##### Correct Option: A

speed of a train in kilometer per hour =45

Speed in meter per second = ( 5/18 ) x Speed in kilometer per hour
= 45 x 5/18
= 12.5 kmph

1. If a motor car covers a distance of 250 m in 25 second, What is its speed in kilometer per hour ?
1. 36.5
2. 36.8
3. 37
4. 36

1. Speed of the motor car in meter per second = 250 / 25
= 10 m/s

Speed in km/hr = (18/5) x speed in m/s

##### Correct Option: D

Speed of the motor car in meter per second = 250 / 25
= 10 m/s

Speed in km/hr = (18/5) x speed in m/s
= 10 x (18 / 5) km/hour
=36 km/hour.

1. A man takes 4 h 20 min in walking to a certain place and riding back. If he walk on both sides he losses 1 h. The time he would take by riding both ways is ?
1. 2 h 20 min
2. 3 h 20 min
3. 2 h
4. 4 h 40 min

1. W + R = 4 h 20 min
W + W = 5 h 20 min

##### Correct Option: B

W + R = 4 h 20 min
W + W = 5 h 20 min
∴ R + R = 3 h 20 min

1. A boat moves downstream at 1 km in 5 minutes and upstream at 1 km in 12 minutes.What is the speed of current?
1. 4.5 km/h
2. 3.5 km/h
3. 2 km/h
4. 2.5 km/h

1. Sd = 12 km/h
Su = 5 km/h
Speed of current = (Sd - Su)/2

##### Correct Option: B

Sd = 12 km/h
Su = 5 km/h
Speed of current = (12 - 5)/2 = 3.5 km/h

1. A person goes to his office from his home at the speed of 4 km/h and return back at the speed of 6 km/h. Find the average speed of the person ?
1. 4.5 km/h
2. 5 km/h
3. 10 km/h
4. 4.8 km/h

1. Average speed = 2ab/(a+b)
= (2 x 4 x 6)/(4 + 6)

##### Correct Option: D

Average speed = 2ab/(a+b)
= (2 x 4 x 6)/(4 + 6)
= 48/10
= 4.8 km/h