A body is projected with a velocity \(u\) with an angle of projection \(\theta.\) The change in velocity after the time \((t)\) from the time of projection will be:
1. | \(gt\) | 2. | \(\frac{1}{2}gt^2\) |
3. | \(u\sin\theta\) | 4. | \(u\cos\theta\) |
A particle has initial velocity and has acceleration . Its speed after 10 s:
1. 7 units
2. units
3. 8.5 units
4. 10 units
The gravity in space is given by . Two particles are simultaneously projected with velocity and . Then, the ratio of their times of flight
1. 1:1
2. 1:2
3. 2:1
4. none
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 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
A train is moving towards east and a car is along north, both with same speed. The observed direction of car to the passenger in the train is
1. East-north direction
2. West-north direction
3. South-east direction
4. None of these
A ball P is dropped vertically and another ball Q is thrown horizontally from the same height and at the same time. If air resistance is neglected, then
1. Ball P reaches the ground first
2. Ball Q reaches the ground first
3. Both reach the ground at the same time
4. The respective masses of the two balls will decide the time
A frictionless wire \(AB\) is fixed on a sphere of radius \(R\). A very small spherical ball slips on this wire. The time taken by this ball to slip from \(A\) to \(B\) is:
1. \(\frac{2 \sqrt{g R}}{g \cos \theta}\)
2. \(2 \sqrt{g R} . \frac{\cos \theta}{g}\)
3. \(2 \sqrt{\frac{R}{g}}\)
4. \(\frac{g R}{\sqrt{g\cos \theta}}\)
A body is slipping from an inclined plane of height \(h\) and length \(l\). If the angle of inclination is \(\theta\), the time taken by the body to come from the top to the bottom of this inclined plane is:
1. \(\sqrt{\frac{2 h}{g}}\)
2. \(\sqrt{\frac{2 l}{g}}\)
3. \(\frac{1}{\sin \theta} \sqrt{\frac{2 h}{g}}\)
4. \(\sin \theta \sqrt{\frac{2 h}{g}}\)