Advertisements
Advertisements
प्रश्न
A car travels 100 km at a speed of 60 km/h and returns with a speed of 40 km/h. Calculate the average speed for the whole journey.
उत्तर
In the first case, the car travels at a speed of 60 km/h for a distance of 100 km.
Thus,
`"Time" = "Distance travelled"/"Speed"`
So , t1 = `100/60` hr
= `5/3` hr
In the second case, the car travels at a speed of 40 km/h for a distance of 100 km.
Thus,
`"Time" = "Distance travelled"/"Speed"`
So , t2 = `100/40` hr
= `5/2` hr
Total time taken :
= t1 + t2
= `5/3 + 5/2` hr
= `25/6` hr
Total distance travelled = 200 km
We can calculate average speed as:
`"Average Speed" = "Tatal Distance travelled"/"Time"`
Average speed for the entire journey :
= `"(200)(6)"/25`
= 48 km/hr
APPEARS IN
संबंधित प्रश्न
What name is given to the speed in a specified direction ?
Arrange the following speed in increasing order (keeping the least speed first):
A bicycle moving with a speed of 200 m/min.
A car is moving along a straight road at a steady speed. It travels 150 m in 5 seconds:
How long does it take to travel 240 m ?
The tip of seconds’ hand of a dock takes 60 seconds to move once on the circular dial of the clock. If the radius of the dial of the clock be 10.5 cm, calculate the speed of the tip of the seconds’ hand of the clock. `("Given" π= 22/7)`.
One of the following is not a vector quantity. This one is :
Give an example of the motion of a body moving with a constant speed but with a variable velocity. Draw a diagram to represent such a motion.
Arrange the following speeds in increasing order.
10 m s-1, 1 km min-1 and 18 km h-1.
A train takes 2 h to reach station B from station A, and then 3 h to return from station B to station A. The distance between the two stations is 200 km. Find:
The average speed,
The average velocity of the train.
A body moves from rest with uniform acceleration and travels 270 m in 3 s. Find the velocity of the body at 10 s after the start.
