A river is flowing with a speed of 1 km/hr. A swimmer wants to go to point 'C' starting from 'A'. He swims with a speed of 5 km/hr, at an angle θ with respect to the river. If AB = BC = 400 m. Then
1. The time taken by the man is 12 min
2. The time taken by the man is 8 min
3. The value of θ is 45°
4. The value of θ is 53°
A body is thrown horizontally with a velocity √2gh from the top of a tower of height h. It strikes the level ground through the foot of the tower at a distance x from the tower. The value of x is:
1. | h | 2. | h2 |
3. | 2h | 4. | 2h3 |
Two men P and Q are standing at corners A and B of a square ABCD of side 8 m. They start moving along the track with a constant speed 2 m/s and 10 m/s respectively. The time when they will meet for the first time is equal to:
1. 2 sec
2. 3 sec
3. 1 sec
4. 6 sec
A particle starts from the origin at t=0 and moves in the x-y plane with constant acceleration 'a' in the y direction. Its equation of motion is y=bx2. The x component of its velocity (at t=0) is:
1. variable
2. √2ab
3. a2b
4. √a2b
A body is projected with a velocity u with an angle of projection θ. The change in velocity after the time (t) from the time of projection will be:
1. | gt | 2. | 12gt2 |
3. | usinθ | 4. | ucosθ |
What determines the nature of the path followed by the particle?
1. Speed only
2. Velocity only
3. Acceleration only
4. None of these
A boat is sent across a river in perpendicular direction with a velocity of 8 km/hr. If the resultant velocity of boat is 10 km/hr, then velocity of the river is :
1. 10 km/hr
2. 8 km/hr
3. 6 km/hr
4. 4 km/hr
A boat is moving with velocity of 3ˆi+4ˆj in river and water is moving with a velocity of −3ˆi−4ˆj with respect to ground. Relative velocity of boat with respect to water is:
1. −6ˆi−8ˆj
2. 6ˆi+8ˆj
3. 8ˆj
4. 6ˆi
A boat moves with a speed of 5 km/h relative to water in a river flowing with a speed of 3 km/h and having a width of 1 km. The minimum time taken around a round trip(returning to the initial point) is:
1. 5 min
2. 60 min
3. 20 min
4. 30 min
A river is flowing from W to E with a speed of 5 m/min. A man can swim in still water with a velocity 10 m/min. In which direction should the man swim so as to take the shortest possible path to go to the south.
1. 30° with downstream
2. 60° with downstream
3. 120° with downstream
4. South