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प्रश्न
Figure ahead represents the displacement - time sketch of motion of two cars A and B . Find :
(i) the distance by which the car B was initially ahead of car A.
(ii) the velocities of car A and car B.
(iii) the time in which car A catches car B.
(iv) the distance from start when the car A will catch the car B.
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उत्तर
(i) Initially, the car B was 40 km ahead of car A.
(ii) Straight line depicts that cars A and B are moving with uniform velocities.
For car A
Displacement at t = 1 h is 40 m
Velocity = Displacement /time
= (40/1) km/h
= 40 km/h-1
For car B
Displacement at t = 4 h is (120 - 40) km, i.e. 80 km
Velocity = Displacement /time
= (80/4) km/h
= 20 km/h-1
(iii) Car A catches car B in 2 hours.
(iv) After starting, car A will catch car B at 80 km.
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| (a) | (b) |
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