Which of the following is true for displacement? (a) It cannot be zero. (b) Its magnitude is greater than the distance travelled by the object. Open Answer »
An artificial is moving in a circular orbit of radius 42250 km. Calculate its speed if it takes 24 hrs to revolve around the earth. Open Answer »
State which of the following situations are possible and give an example of each of the following: (a) an object with a constant acceleration but with zero velocity, (b) an object moving in a certain direction with an acceleration in the perpendicular direction. Open Answer »
The speed – time graph for a car is shown in Figure:(a) Find how far does the car travel in the first 4 seconds. Shade the area on the graph that represents the distance travelled by the car during the period. (b) Which part of the graph represents uniform motion of the car? Open Answer »
A ball is gently dropped from a height of 20 m. If its velocity increases uniformly at the rate of 10ms-2 , with what velocity will it strike the ground? After what time will it strike the ground? Open Answer »
Fig 8.11 shows the distance-time graph of three objects A, B and C. Study the graph and answer the following questions:(a) Which of the three is travelling the fastest? (b) Are all three ever at the same point on the road? (c) How far has C travelled when B passes A? (d) How far has B travelled by the time it passes C? Open Answer »
A driver of a car travelling at 52 kmh-1 applies the brakes and accelerates uniformly in the opposite direction. The car stops after 5 s. Another driver going at 34 kmh-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 two cars. Which of the two cars travelled farther after the brakes were applied? Open Answer »
Abdul, while driving to school, computes the average speed for his trip to be 20 kmh-1 . On his return trip along the same route, there is less traffic and the average speed is 30 kmh-1 . What is the average speed of Abdul’s trip? Open Answer »
Joseph jogs from one end A to another end B of a straight 300 m road in 2 minutes and 30 sec 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 (b) from A to C? Open Answer »
An athlete completes one round of circular track of diameter 200 m in 40 sec. What will be the distance covered and the displacement at the end of 2 minutes 20 sec? Open Answer »