A body is executing uniform circular motion in a circle of radius 100 m at speed 10 m/s. Acceleration of the body is :
(1) Zero
(2) 2
(3) 1
(4) 5
A particle started revolving from rest with a constant angular acceleration in a circular path of radius r. If centripetal acceleration becomes numerically equal to tangential acceleration at time t, then t is equal to:
1.
2.
3.
4.
Balls A and B are thrown simultaneously from two points lying on the same horizontal plane separated by a distance 120 m. Path of A w.rt. B is
(1) Parabola
(2) Hyperbola
(3) Circle
(4) Straight line
Which of the following is the angle between velocity and acceleration of a body in uniform circular motion?
1. \(30^\circ\)
2. \(45^\circ\)
3. \(60^\circ\)
4. \(90^\circ\)
A man wants to cross a river of width 500 m in the minimum distance. The rowing speed of man relative to water is 3 km/h and river flows with speed 2 km/h. The time taken by the man to cross the river
(1) 2 minute
(2) 6 minute
(3) 2 minute
(4) 6 minute
A person is rotating in a horizontal circle of radius 7 m. Find the period of rotation for which the acceleration is equal to 3g.
(1) 2.6 s
(2) 2.8 s
(3) 3.1 s
(4) 4.3 s
A man can row a boat with a speed of \(10\) kmph in still water. The river flows at \(6\) kmph. If he crosses the river from one bank to the other along the shortest possible path, time taken to cross the river of width \(1\) km is:
1. \(\frac{1}{8}~\text{h}\)
2. \(\frac{1}{4}~\text{h}\)
3. \(\frac{1}{2}~\text{h}\)
4. \(1~\text{h}\)
A bus is going to the North at a speed of \(30\) kmph. It makes a \(90^{\circ}\) left turn without changing the speed. The change in the velocity of the bus is:
1. | \(30\) kmph towards \(W\) |
2. | \(30\) kmph towards \(S\text-W\) |
3. | \(42.4\) kmph towards \(S\text-W\) |
4. | \(42.4\) kmph towards \(N\text-W\) |
Two bullets are fired simultaneously horizontally and at different speeds from the same place. Which bullet will hit the ground first? (Air resistance is neglected)
1. | The faster one |
2. | The slower one |
3. | Depends on masses |
4. | Both will reach simultaneously |
A pilot is supposed to fly east from A to B and back again A due west. If the wind is blowing due south, find time for the round trip, if AB = l. The velocity of the plane in the air is v and the velocity of wind is u.
1.
2.
3.
4.