Advertisements
Advertisements
प्रश्न
Distance between Bholu’s and Golu’s house is 9 km. Bholu has to attend Golu’s birthday party at 7 o’clock. He started from his home at 6 o’clock on his bicycle and covered a distance of 6 km in 40 minutes. At that point, he met Chintu and he spoke to him for 5 minutes and reached Golu’s birthday party at 7 o’clock. With what speed did he cover the second part of the journey? Calculate his average speed for the entire journey.
Advertisements
उत्तर
Distance between Bholu’s and Golu’s house = 9 km
Distance covered by Bholu in first part of the journey = 6 km
Time taken to cover 6 km = 40 min
Distance covered by Bholu in second part of the journey = 9 − 6 = 3 km
Time taken to cover 3 km = 60 – (40 + 5) = 15 min
Speed of Bholu while covering second part of the journey
= `(3 "km")/((15/60)"h")`
= 12 km/h
Average speed of Bholu for the entire journey
= `("Total distance")/("Time taken")`
= `(9 "km")/(60 "min")`
= 9 km/h
APPEARS IN
संबंधित प्रश्न
What is the nature of the distance-time graphs for uniform and non-uniform motion of an object?
A driver of a car travelling at 52 km h−1 applies the brakes and accelerates uniformly in the opposite direction. The car stops in 5 s. Another driver going at 3 km h−1 in another car applies his brakes slowly and stops in 10 s. On the same graph paper, plot the speed versus time graphs for the two cars. Which of the two cars travelled farther after the brakes were applied?
The speed-time graph for a car is shown in the following figure:

- Find how far the car travels in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period.
- Which part of the graph represents uniform motion of the car?
A cyclist is travelling at 15 m s-1. She applies brakes so that she does not collide with a wall 18 m away. What deceleration must she have ?
The graph given alongside shows the positions of a body at different times. Calculate the speed of the body as it moves from :
(1) A to B,
(2) B to C, and
(3) C to D.

A student draws a distance-time graph for a moving scooter and finds that a section of the graph is horizontal line parallel to the time axis. Which of the following conclusion is correct about this section of the graph?
Two friends leave Delhi for Chandigarh in their cars. A starts at 5 am and moves with a constant speed of 30 km/h, whereas B starts at 6 am and moves with a constant speed of 40 kmh-1. Plot the distance-time graph for their motion and find at what time the two friends will meet and at what distance from Delhi.
Show the shape of the distance – time graph for the motion in the following cases.
- A bus moving with a constant speed.
- A car parked on a road side.
If we denote speed by S, distance by D and time by T, the relationship between these quantities is ______.
What do you infer if
- Distance – time graph is a straight line.
- The velocity-time graph is curved.
- Displacement time is zigzag.
