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
Abdul, while driving to school, computes the average speed for his trip to be 20 km h−1. On his return trip along the same route, there is less traffic and the average speed is 30 km h−1. What is the average speed for Abdul’s trip?
What do the following measure in a car ?
(a) Speedometer (b) Odometer
Under which condition is the magnitude of average velocity equal to average speed ?
Fill in the following blank with suitable word:
The physical quantity which gives both, the speed and direction of motion of a body is called its……………
Bus X travels a distance of 360 km in 5 hours whereas bus Y travels a distance of 476 km in 7 hours. Which
bus travels faster ?
If a sprinter runs a distance of 100 metres in 9.83 seconds, calculate his average speed in km/h.
Which of the following could not be a unit of speed?
When is a body said to be in motion?
Express 15 m s-1 in km h-1.
A car travels the first 30 km with a uniform speed of 60 km h−1 and the next 30 km with a uniform speed of 40 km h−1. Calculate :
- The total time of journey,
- The average speed of the car.
