**NEET Physics Chapter Wise Mock Test – Circular Motion**

**Question 1:
**A car wheel is rotated to uniform angular acceleration about its axis. Initially its angular velocity is zero. It rotates through an angle θ

_{1}in the first 2s, in the next 2s, it rotates through an additional angle θ

_{2}, the ratio of θ

_{2}/θ

_{1}is

(a) 1

(b) 2

(c) 3

(d) 5

**Question 2:
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**Question 3:
**When a ceiling fan is switched off its angular velocity reduces to 50% while it makes 36 rotations. How many more rotation will it make before coming to rest? (Assume uniform angular retardation)

(a) 18

(b) 12

(c) 36

(d) 48

**Question 4:
**A 70 kg man stands in contact against the inner wall of a hollow cylindrical drum of radius 3 m rotating about its vertical axis with 200 rev/min. The coefficient of friction between the wall and his clothing is 0.15. When the floor is suddenly removed, what is the minimum rotational speed of the cylinder to enable the man to remain stuck to the wall without falling (approximately)?

(a) 5 rad/s

(b) 10 rad/s

(c) 15 rad/s

(d) 20 rad/s

**Question 5:
**A particle of mass 100 g tied to a string is rotated along a circle of radius 0.5 m. The breaking tension of string is 10 N. The maximum speed with which particle can be rotated without breaking the string is

(a) 10 ms

^{-1}

(b) 9.8 ms

^{-1}

(c) 7.7 ms

^{-1}

(d) 7.07 ms

^{-1}

**Question 6:
**Two wheels having radii in the ratio 1:3 are connected by a common belt. If the smaller wheel is accelerated from rest at a rate 1.5 rad s

^{-2 }for 10 s. The velocity of bigger wheel is :

(a) 5 rad s

^{-1}

(b) 15 rad s

^{-1}

(c) 45 rad s

^{-1}

(d) None of these

**Question 7:
**A coin placed on a rotating turn table just slips, if it is placed at a distance of 8 cm from the centre. If angular velocity of the turn table is doubled, it will just slip at a distance of

(a) 1 cm

(b) 2 cm

(c) 4 cm

(d) 8 cm

**Question 8:
**The string of a pendulum is horizontal. The mass of bob attached to it is m. Now, the string is released. The tension in the string in the lowest position is

(a) mg

(b) 2mg

(c) 3mg

(d) 4mg

**Question 9:
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**Question 10:
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**Question 11:
**A heavy stone hanging from a massless string of length 15m is projected horizontally with speed 147 m/s. The speed of the particle at the point where the tension in the string equals the weight of the particle is

(a) 10 ms

^{-1}

(b) 7ms

^{-1}

(c) 12 ms

^{-1}

(d) None of these

**Question 12:
**A stone of mass 1 kg is tied to a string 4 m long and is rotated at constant speed of 40 ms

^{-1}in a vertical circle. The ratio of the tension at the top and the bottom is (take, g = 10 ms

^{-2})

(a) 11:12

(b) 39: 41

(c) 41:39

(d) 12:11

**Question 13:
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**Question 14:
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**Question 15:
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**Question 16:
**A particle is kept at rest at the top of a sphere of diameter 42m. When disturbed slightly, it slides down. At what height h from the bottom, the particle will leave the sphere?

(a) 14 m

(b) 28m

(c) 35m

(d) 7m

**Question 17:
**For a particle in a non-uniform accelerated circular motion correct statement is

(a) velocity is radial and acceleration is transverse

(b) velocity is transverse and acceleration is radial only

(c) velocity is radial and acceleration has both radial and transverse components

(d) velocity is transverse and acceleration has both radial and transverse components

**Question 18:
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**Question 19:
**An aircraft executes a horizontal loop of radius 1 km with a speed of 900 kmh

^{-1}. Ratio of centripetal acceleration to acceleration due to gravity is

(a) 12.3

(b) 3.3

(c) 6.4

(d) None of these

**Question 20:
**A boy whirls a stone in a horizontal circle of radius 1.5 m and at height 2.0 m above level ground. The string breaks and the stone flies off tangentially and strikes the ground after travelling a horizontal distance of 10 m. What is the magnitude of the centripetal acceleration of the stone while in circular motion?

(a) 163 ms

^{-2}

(b) 64 ms

^{-2}

(c) 15.63 ms

^{-2}

(d) 125 ms

^{-2}

**Question 21:
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**Question 22:
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**Question 23:
**A cyclist is riding with a speed of 27 km/h. As he approaches a circular turn on the road of radius 80 m, he applies brakes and reduces his speed at the constant rate of 0.5 m/s every second: What is the magnitude and direction of the net acceleration of the cyclist on the circular turn?

(a) 0.5 m/s

^{2}

(b) 0.86 m/s

^{2}

(c) 0.72 m/s

^{2}

(d) 0.3 m/s

^{2}

**Question 24:
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**Question 25:
**A national roadway bridge over a canal is in the form of an arc of a circle of radius 49 m. What is the maximum speed with which a car can move without leaving the ground at the highest point?

(take, g = 9.8 ms

^{-2})

(a) 19.6 ms

^{-1}

(b) 40ms

^{-1}

(c) 22 ms

^{-1}

(d) None of these

**Question 26:
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**Question 27:
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**Question 28:
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**Question 29:
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**Question 30:
**A car of mass 1000 kg negotiates a banked curve of radius 90 m on a frictionless road. If the banking angle is 45°, the speed of the car is

(a) 20 ms

^{-1}

(b) 30 ms

^{-1}

(c) 5ms

^{-1}

(d) 10ms

^{-1}

**Question 31:
**A particle moves in a circle of radius 5 cm with constant speed and time period 0.2 π s. The acceleration of the particle is

(a) 25 m/s

^{2}

(b) 36 m/s

^{2}

(c) 5m/s

^{2}

(d) 15 m/s

^{2}

**Question 32:
**Find the maximum velocity with which a train can be moved on a circular track of radius 200m. The banking of the track is 5.71° (Given, tan 5.71° = 0.1)

(a) 1.4 m/s

(b) 14 m/s

(c) 140 m/s

(d) 0.14 m/s

**Question 33:
**A 1 kg stone at the end of 1 m long string is whirled in a vertical circle at constant speed of 4m/s. The tension in the string is 6 N, when the stone at

(take, g = 10 m/s

^{2}).

(a) top of the circle

(b) bottom of the circle

(c) half way down

(d) None of the above

**Question 34:
**A car is moving in a circular horizontal track of radius 10.0 m with a constant speed of 10.0 ms

^{-1}. A plumb bob is suspended from the roof of the car by a light rigid rod of length 1.00 m. The angle made by the rod with the track is (take, g = 10 ms

^{-2}).

(a) zero

(b) 30°

(c) 45°

(d) 60°

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