Which of the following four statements is false?
1. A body can have zero velocity and still be accelerated.
2. A body can have a constant velocity and still have a varying speed.
3. A body can have a constant speed and still have a varying velocity.
4. The direction of the velocity of a body can change when its acceleration is constant.
The position of a particle moving in the XY plane at any time t is given by metres. Select the correct statement about the moving particle from the following.
1. The acceleration of the particle is zero at t = 0 second
2. The velocity of the particle is zero at t = 0 second
3. The velocity of the particle is zero at t = 1 second
4. The velocity and acceleration of the particle are never zero
If body having initial velocity zero is moving with uniform acceleration 8 m/sec2 , then the distance travelled by it in fifth second will be
1. 36 metres
2. 40 metres
3. 100 metres
4. Zero
An alpha particle enters a hollow tube of 4 m length with an initial speed of 1 km/s. It is accelerated in the tube and comes out of it with a speed of 9 km/s. The time for which it remains inside the tube is
1.
2.
3.
4.
Two cars and are travelling in the same direction with velocities and . When the car is at a distance behind car , the driver of the car applied the brake producing uniform retardation . There will be no collision when:
1.
2.
3.
4.
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 axis and along the axis. Its distance from the origin after seconds will be:
1.
2.
3.
4.
A car moving with a velocity of 10 m/s can be stopped by the application of a constant force F in a distance of 20 m. If the velocity of the car is 30 m/s, it can be stopped by this force in
1.
2. 20 m
3. 60 m
4. 180 m
The displacement of a particle is given by . The initial velocity and acceleration are, respectively:
1. | 2. | ||
3. | 4. |