IITJEE physics:Kinematics multiple choice questions(MCQ)

IITJEE physics:Kinematics multiple choice questions(MCQ)



1. A particle traveled half the distance with a velocity v1. The remaining part of the distance was covered with velocity v2 for half the time and with velocity v3 for the other half of the time. The average velocity over the whole time of motion is

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2. Two cars move in the same straight line starting at the same moment from the same point in it; the first
moves with constant velocity u and the second with constant acceleration a; during the time that elapses before the
second catches the first. The greatest distance between the particle at the end of time u/a from the start. (Solve the
problem both ways with and without the aid of calculus).

(a) u2/a
(b) u2/4a
(c) u2/2a
(d) none of these

3. Two ships are 10 km apart on a line running south to north. The one farther north is streaming west at
40 km/hr. The other is steaming north at 40 km/hr. The distance of closest approach and how long do they take to
reach itare is

(a) 7.071 km, 1/2 hr
(b) 7.071 km, 1/8 hr
(c) 6 km, 1/8 hr
(d) none of these

4. Two boats A and B move away from a buoy anchored at the middle of a river along mutually perpendicular straight lines. The boat A moves along the stream and the boat B across the river. After moving off an equal distance of 500 m from the buoy, both the boats return to their original positions. The ratio of the time taken by boat A to that taken by boat B if the velocity of each boat with respect to water is 20 ms–1 and the stream velocity is 10 ms–1.

(a) 2
(b) 1.155
(c) 1
(d) 2.5

5. A particle is projected with velocity 2 (hg)1/2 to that it is just clears two walls of equal height h which are at a distance 2h from each other. The time dt of passing between the walls is

(a) 2(h/g)1/2
(b) 2(g/h)1/2
(c) 4(g/h)1/2
(d) 4(h/g)1/2