A motor cyclist moving with a velocity of 72 km/hour on a flat road takes a turn on the road at a point where the radius of curvature of the road is 20 meters. The acceleration due to gravity is 10 m/sec2. In order to avoid skidding, he must not bend with respect to the vertical plane by an angle greater than
(1)
(2)
(3)
(4)
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
(1) Proportional to r2
(2) Independent of r
(3) Proportional to r
(4) Proportional to 1/r
Two masses M and m are attached to a vertical axis by weightless threads of combined length l. They are set in rotational motion in a horizontal plane about this axis with constant angular velocity ω. If the tensions in the threads are the same during motion, the distance 'x' of M from the axis is-
(1)
(2)
(3)
(4)
A 500 kg car takes a round turn of radius 50 m with a velocity of 36 km/hr. The centripetal force is
(1) 250 N
(2) 750 N
(3) 1000 N
(4) 1200 N
A ball of mass 0.25 kg attached to the end of a string of length 1.96 m is moving in a horizontal circle. The string will break if the tension is more than 25 N. What is the maximum speed with which the ball can be moved
(1) 14 m/s
(2) 3 m/s
(3) 3.92 m/s
(4) 5 m/s
A body of mass 5 kg is moving in a circle of radius 1m with an angular velocity of 2 radian/sec. The centripetal force is
(1) 10 N
(2) 20 N
(3) 30 N
(4) 40 N
A stone of mass of 16 kg is attached to a string 144 m long and is whirled in a horizontal circle. The maximum tension the string can withstand is 16 Newton. The maximum velocity of revolution that can be given to the stone without breaking it will be-
(1) 20 ms–1
(2) 16 ms–1
(3) 14 ms–1
(4) 12 ms–1
Find the maximum velocity for skidding for a car moved on a circular track of radius 100 m. The coefficient of friction between the road and tyre is 0.2
(1) 0.14 m/s
(2) 140 m/s
(3) 1.4 km/s
(4) 14 m/s
A ball of mass \(0.1~\text{kg}\) is whirled in a horizontal circle of radius \(1\) m by means of a string at an initial speed of \(10~\text{rpm}\) . Keeping the radius constant, the tension in the string is reduced to one quarter of its initial value. The new speed is:
1. | \(5~\text{rpm}\) | 2. | \(10~\text{rpm}\) |
3. | \(20~\text{rpm}\) | 4. | \(14~\text{rpm}\) |
A cyclist riding the bicycle at a speed of ms–1 takes a turn around a circular road of radius m without skidding. Given g = 9.8 ms–2, what is his inclination to the vertical?
(1) 30o
(2) 90o
(3) 45o
(4) 60o