Class Notes NCERT Solutions for CBSE Students
question: Joseph jogs one end A to the other end B of a straight 300 m road in 2 minutes 30 seconds and then turns around and jogs 100 m back to point C in another 1 minute. What are joseph’s average speeds and velocities in jogging (a) from A to B and (b) from A to C?
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Question: 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?
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Question: A motorboat from rest on a lake accelerates in a straight line at a constant rate of 3.0 ms-2 for 8.0 s. How far does the boat travel during this time?
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Question: 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 care 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 traveled farther after the brakes were applied?
Distance covered by first driver = 1/2 × 14.44 × 5 = 36.1 m
Distance covered by second driver = 1/2 × 0.8333 × 10 = 4.165 m
Hence, distance travelled by first car is more.
