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प्रश्न
Figure (a) shows the displacement-time graph for the motion of a body. Use it to calculate the velocity of the body at t = 1 s, 2 s and 3 s, and then draw the velocity-time graph in Figure (b) for it.
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| (a) | (b) |
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उत्तर
We observe from the given displacement time graph above, that the slope is a straight line inclined with time axis, so the body is moving with uniform velocity.
velocity = Slope of straight line
t = 1; velocity = `2/1` = 2 m/s
t = 2; velocity = `4/2` = 2 m/s
t = 3; velocity = `6/3` = 2 m/s
Hence, velocity at t = 1 s, 2 s and 3 s is equal to 2 m s-1
Velocity-time graph for the motion of a body is given below:
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संबंधित प्रश्न
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?
Fill in the following blank with suitable word :
The slope of a distance-time graph indicates ………………….. of a moving body.
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A body moves along a straight road with a speed of 20 m/s and has a uniform acceleration of 5 m/s2. What will be its speed after 2 s?
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.
Complete the data of the table given below with the help of the distance-time graph given in the figure.
| Distance (m) | 0 | 4 | ? | 12 | ? | 20 |
| Time (s) | 0 | 2 | 4 | ? | 8 | 10 |
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.
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