A body of mass 10 kg is moving with a constant velocity of 10 m/s. When a constant force acts for 4 seconds on it, it moves with a velocity 2 m/sec in the opposite direction. The acceleration produced in it is
(1) 3 m/sec2
(2) –3 m/sec2
(3) 0.3 m/sec2
(4) –0.3 m/sec2
A body starts from rest from the origin with an acceleration of along the x-axis and along the y-axis. Its distance from the origin after 4 seconds will be
(1) 56 m
(2) 64 m
(3) 80 m
(4) 128 m
The displacement of a particle is given by . The initial velocity and acceleration are, respectively:
1. | \(\mathrm{b}, ~\mathrm{-4d}\) | 2. | \(\mathrm{-b},~ \mathrm{2c}\) |
3. | \(\mathrm{b}, ~\mathrm{2c}\) | 4. | \(\mathrm{2c}, ~\mathrm{-2d}\) |
A car moving with a speed of 40 km/h can be stopped by applying brakes for atleast 2 m. If the same car is moving with a speed of 80 km/h, what is the minimum stopping distance ?
(1) 8 m
(2) 2 m
(3) 4 m
(4) 6 m
The displacement is given by , the acceleration at is
(1)
(2)
(3)
(4)
A body moves from rest with a constant acceleration of 5 m/s2. Its instantaneous speed (in m/s) at the end of 10 sec is
(1) 50
(2) 5
(3) 2
(4) 0.5
If a car at rest accelerates uniformly to a speed of 144 km/h in 20 s. Then it covers a distance of
(1) 20 m
(2) 400 m
(3) 1440 m
(4) 2880 m
If a train travelling at 72 kmph is to be brought to rest in a distance of 200 metres, then its retardation should be
(1) 20 ms–2
(2) 10 ms–2
(3) 2 ms–2
(4) 1 ms–2
The displacement of a particle starting from rest (at t = 0) is given by . The time in seconds at which the particle will attain zero velocity again, is
(1) 2
(2) 4
(3) 6
(4) 8
Two cars A and B are at rest at the same point initially. If A starts with uniform velocity of 40 m/sec and B starts in the same direction with a constant acceleration of 4 m/s2, then B will catch A after how much time?
(1) 10 sec
(2) 20 sec
(3) 30 sec
(4) 35 sec