10 Question and answer on motion in one dimension
1. A particle starts from the origin, goes along X –axis to the point (20m, 0) and then returns along the same line to the point (-20m, 0). The distance and displacement of the particle during the trip are:
(a) 40m, 0
(b) 40m, 20m
(c) 40m, -20
(d) 60m, -20m
Ans : (d)
2. When two bodies move uniformly towards each other the distance between then decreases by 8 m/s. If both bodies move in the same direction with different speeds the distance between them increases by 2m/s. The speeds of two bodies will be-
(a) 4m/s and 3m/s
(b) 4m/s and 2m/s
(c) 5m/s and 3m/s
(d) 7m/s and 3m/s
Ans:( c)
3. A particle moves in the direction of east or 2s with velocity of 15ms-1 then move towards north for 8 s with a velocity of 5ms-1 . The average velocity of the particle is
(a) 1ms-1
(b) 5ms-1
(c) 7ms-1
(d) 10ms-1
Ans : (b)
4. An aeroplane moves 400m towards north, 300 m towards west and then 1200 m vertically upwards. Then its displacement from the initial position is
(a) 1300 m
(b) 1400 m
(c) 1500 m
(d) 1600 m
Ans: (a)
5. If distance covered by a particle is zero, what can you say about its displacement?
(a) It may or may not be zero
(b) It cannot be zero
(c) It is negative
(d) It must be zero
Ans: (d)
6. A car runs between two station A and B. From A to B, it goes with a speed of 30 km/h and from B to A it returns to 40 km/h. The average speed of the car between A and B is:
(a) 35 km/h
(b) 34.5 km/h
(c) 34.3 km/h
(d) 10 km/h
Ans: (c)
7. A bus travels the first one third distance at a speed of 10 km/h. The next one third distance at 20 km/h and the last one third distance at 60 km/h. The average speed of the bus is
(a) 16 km/h
(b) 18 km/h
(c) 9 km/h
(d) 48 km/h
Ans: (b)
8. If displacement of a particle is zero, distance covered by it.
(a) May be zero or may not be zero
(b) Must be zero
(c) Must not be zero
(d) All are true
Ans:(a)
9. A bus travelling, the first one third distance at a speed of 10 km/h, the next one forth at 20 km/h and the remaining at40 km/h,The average speed of the bus is nearly
(a) 9 km/h
(b) 16 km/h
(c) 18 km/h
(d) 48 km/h
Ans: (c)
10. A car moves a distance of 200 m. It covers the first half of the distance at speed 40 km/h and the second half of distance at speed v. The average speed is 48 km/h . Find the value of v.
(a) 56 km/h
(b) 60 km/h
(c) 50 km/h
(d) 48 km/h
Ans: (b)