Advertisements
Advertisements
प्रश्न
A motorcyclist drives from A to B with a uniform speed of 30 km h–1 and returns back with a speed of 20 km h–1. Find its average speed.
Advertisements
उत्तर
Let the distance between A and B be S km.
Time taken in going from A to B = `"s"/30 "h"`
Time taken in going from B to A = `"s"/20 "h"`
Average speed of motorcyclist = `"total distance covered"/"total time taken"`
= `("S km" + "S km")/("S"/30"h" + "S"/20"h")`
= `2/(1/30 + 1/20) "km h^-1"`
= `2/(1/12) "km h"^-1`
= 24 km h−1
APPEARS IN
संबंधित प्रश्न
Under what condition(s) is the magnitude of average velocity of an object equal to its average speed?
What do the following measure in a car ?
(a) Speedometer (b) Odometer
Convert a speed of 54 km/h into m/s.
A car is moving along a straight road at a steady speed. It travels 150 m in 5 seconds:
How far does it travel in 6 seconds ?
A car is moving on a straight road with uniform acceleration. The speed of the car varies with time as follows :
Time (s) : 0 2 4 6 8 10
Speed (m/s) : 4 8 12 16 20 24
Draw the speed-time graph by choosing a convenient scale. From this graph :

(1) Calculate the acceleration of the car.
(2) Calculate the distance travelled by the car in 10 seconds.
A car moving on a straight path covers a distance of 1 km due east in 100 s. What is velocity of the car?
A train travels with a speed of 60 km h-1 from station A to station B and then comes back with a speed 80 km h-1 from station B to station A. Find -
- The average speed
- The average velocity of the train.
A speeding car changes its velocity from 108 kmh−1 to 36 kmh−1 in 4 s. Calculate its deceleration in
- ms−2
- kmh−2.
Write down the type of motion of a body along with the A – O – B of the following distance – time graph.

Define speed of a body.
