On horizontal smooth surface a mass of 2 kg is whirled in a horizontal circle by means of a string at an initial angular speed of 5 revolutions per minute. Keeping the radius constant the tension in the string is doubled. The new angular speed is nearly:
A coin placed on a rotating turntable just slips if it is placed at a distance of 4 cm from the centre. If the angular velocity of the turntable is doubled , it will just slip at a distance of
A string breaks if its tension exceeds 10 newtons. A stone of mass 250 gm tied to this string of length 10 cm is rotated in a horizontal circle. The maximum angular velocity of rotation can be.
A particle moving along a circular path due to a centripetal force having constant magnitude is an example of motion with :
A stone of mass 0.5 kg tied with a string of length 1 metre is moving in a circular path with a speed of
4 m/sec. The tension acting on the string in newton is –
A stone is moved round a horizontal circle with a 20 cm long string tied to it. If centripetal acceleration is 9.8 m/sec2, then its angular velocity will be
A particle of mass m is executing a uniform motion along a circular path of radius r. If the magnitude of its linear momentum is p, the radial force acting on the particle will be
A particle moves in a circular orbit under the action of a central attractive force inversely proportional to the distance ‘r’. The speed of the particle is.
A particle of mass m is moving in a horizontal circle of radius r under a centripetal force equal to –k/r². The total kinetic energy of the particle is-
A 500 kg car takes around turn of radius 50 m with a speed of 36 km/hr. The centripetal force acting on the car will be :
If the radii of circular paths of two particles of same masses are in the ratio of 1 : 2, then in order to have same centripetal force, their speeds should be in the ratio of :
A particle is moving in a horizontal circle with constant speed. It has constant
A gramophone recorder rotates at angular velocity of ω a coin is kept at a distance r from its centre. If μ is static friction constant then coil will rotate with gramophone if -
A cyclist is moving on a circular track of radius 80 m with a velocity of 72 km/hr. He has to lean from the vertical approximately through an angle –
A mass is supported on a frictionless horizontal surface. It is attached to a string and rotates about a fixed centre at an angular velocity w0. If the length of the string and angular velocity are doubled, the tension in the string which was initially T0 is now –
A stone tied to the end of a string of 1 m long is whirled in a horizontal circle with a constant speed. If the stone makes 22 revolutions in 44 s, what is the magnitude and direction of acceleration of the stone ?
A cylindrical vessel partially filled with water is rotated about its vertical central axis. It’s surface will
A motorcycle is going on an overbridge of radius R. The driver maintains a constant speed. As the motorcycle is ascending on the overbridge, the normal force on it :
In a circus, stuntman rides a motorbike in a circular track of radius R in the vertical plane. The minimum speed at highest point of track will be :
A particle is moving in a vertical circle. The tensions in the string when passing through two positions at angles 30° and 60° from vertical (lowest positions) are T1 and T2 Then
A heavy mass is attached to a thin wire and is whirled in a vertical circle. The wire is most likely to break.
A hollow sphere has radius 6.4 m. Minimum velocity required by a motor cyclist at bottom to complete the circle will be.
A body of mass 100 g is rotating in a circular path of radius r with constant speed. The work done in one complete revolution is.
A weightless thread can bear tension upto 3.7 kg wt. A stone of mass 500 gms is tied to it and revolved in a circular path of radius 4 m in a vertical plane. If g = 10 ms–2, then the maximum angular velocity of the stone will be.
A small disc is on the top of a hemisphere of radius R. What is the smallest horizontal velocity v that should be given to the disc for it to leave the hemisphere and not slide down it ? [There is no friction]