A train is moving with a speed of 72 km/h. What is its speed in m/s?
Given,
Velocity = 72 km/hr
So,
Velocity in m/s will be given by,
v =
A car goes from a town A to another town B with a speed of 40 km/h and returns back to the town A with a speed of 60 km/h. Calculate the average speed during the whole journey.
Let the total distance travelled to and fro be d
Speed while ging from town A to town B = 40 km/hr
Speed while coming back from town B to town A = 60 km/hr
Time taken to go to town B ,t1 =
t1 =
Time taken to return to town A, t2 =
Average speed =
A car covers the first half of the distance between two places at a speed of 40 km/h and the second half at 60 km/h. What is the average speed of the car?
Let, the total distance covered the car be 'd'.
Given,
Speed in the first half = 40 km/hr
Speed in the second half of distance = 60 km/hr
Let the time taken by the car in the first half = t1
Therefore,
Time,
Time taken by car in the second half, t2 =
Now, average speed =
A train 40 m long passes over a bridge 200 m long at a speed of 36 km/h. How long will it take to pass completely over the bridge?
Length of the train = 40 m = 0.04 km
Length of the bridge = 200 m = 0.2 km
Speed of the train = 36 km/hr
The total time taken by the train to completely pass over the bridge is given by time for the front of the train to travel 200 m at 36 km/hr + time for the back of train to travel 40 m at a speed of 36 km/hr.
Therefore,
Total time taken =
A car travels 270 km in 4.5 hours. Calculate:
(i) its speed;
(ii) how far will it go in 7 hours at this speed; and
(iii) how long will it take to travel 300 km at this speed.
Given,
Distance travelled by the car = 270 km
Total time for travel = 4.5 hours
i) Speed of the car, v =
=
ii) Speed = 60 km/hr
Time taken = 7 hours
Distance travelled =
= 420 km
(iii) Speed = 60 km/hr
Distance to be travelled = 300 km
Time taken =
=