**NEET Physics Chapter Wise Mock Test – Mechanics**

**Question 1:
**Imagine a light planet revolving around a very massive star in a circular orbit of radius R with a period of revolution T. If the gravitational force of attraction between the planet and the star is inversely proportional to R

^{5/2}then T

^{2}is proportional to

(a) R

^{3}

(b) R

^{7/2}

(c) R

^{3/2}

(d) R

^{3.75}

**Question 2:
**The escape velocity from the earth’s surface is 11kms

^{-1}. A certain planet has a radius twice that of the earth but its mean density is the same as that of the earth. The value of the escape velocity from this planet would be

(a) 22 kms

^{-1}

(b) 11 kms

^{-1}

(c) 5.5 kms

^{-1}

(d) 16.5 kms

^{-1}

**Question 3:
**If R is the radius of the earth and g is the acceleration due to gravity on the earth’s surface, the mean density of the earth is

(a) 4ΠG/3gR

(b) 3ΠG/4gR

(c) 3g/4ΠRG

(d) ΠRg/12G

**Question 4:
**The product of pressure and volume have the Same units as the product of

(a) charge and potential

(b) electric field strength and distance

(c) electromotive force and capacitance

(d) magnetic moment and magnetic induction

**Question 5:
**The radius of a ball is (5.2 ±0.2) cm. The percentage error in the volume of the ball is approximately

(a) 11%

(b) 4%

(c) 7%

(d) 9%

**Question 6:
**If the error in the measurement of momentum of a particle is (+100%), then the error in the measurement of kinetic energy is

(a) 100%

(b) 200%

(c) 300%

(d) 400%

**Question 7:
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**Question 8:
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**Question 9:
**A boat which has a speed of 5 kmh

^{-1}in still water crosses a river of width 1 km along the shortest path in 15 min. The velocity of the river in kmh

^{-1 }is

(a) 1

(b) 3

(c) 4

(d) √41

**Question 10:
**The velocity of a particle at an instant is 10 ms

^{-1}and after 5 s the velocity of the particle is 20 ms

^{-1}. The velocity 3 s before in ms

^{-1}was

(a) 8

(b) 4

(c) 6

(d) 7

**Question 11:
**A particle moving in a straight line covers half the distance with speed of 3 ms

^{-1}. The other half of the distance is covered in two equal time intervals with speed of 4.5 ms

^{-1}and 7.5 ms

^{-1}, respectively. The average speed of the particle during this motion is

(a) 4.0 ms

^{-1}

(b) 5.0 ms

^{-1}

(c) 5.5 ms

^{-1}

(d) 4.8 ms

^{-1}

**Question 12:
**What will be the ratio of the distance moved by a freely

falling body from rest in 4th and 5th seconds of journey?

(a) 4 :5

(b) 7:9

(c) 16:25

(d) 1:1

**Question 13:
**A particle moves in xy-plane according to the equation x = 4t

^{2}+ 5t+ 16 and y = 5t The acceleration of the particle is

(a) 8

(b) 13

(c) 14

(d) 16

**Question 14:
**A body starts from rest, what is the ratio of the distance travelled by the body during the 4th second and 3rd second?

(a) 7/5

(b) 5/7

(c) 7/3

(d) 3/7

**Question 15:
**A particle moves along the X-axis such that its coordinate (x) varies with time (t), according to the expression x=2-5t+6t

^{2}, where x is in metre and t is in second. The initial velocity of the particle is

(a) -5 ms

^{-1}

(b) -3 ms

^{-1}

(c) 6 ms

^{-1}

(d) 2 ms

^{-1}

**Question 16:
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**Question 17:
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**Question 18:
**A particle moves from position = 3i + 2j — 6 k to position r2 =14i + 13j+9k under the action of force (4i + j + 3k) N. The work done will be

(a) 100 J

(b) 50 J

(c) 200 J

(d) 75 J

**Question 19:
**An elevator car whose floor to ceiling distance is equal to 2.7 m starts ascending with constant acceleration of 1.2 ms-2. After 2 s of the start, a bolt begins falling from the ceiling of the car. The free fall time of the bolt is

(a) √6 s

(b) 0.7 s

(c) 1s

(d) √0.54 s

**Question 20:
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**Question 21:
**A block slides from an inclination of 45°. If it takes time twice ‘with friction than to that without friction, then coefficient of friction for surface is given by

(a) 1

(b) 0.75

(c) 0.5

(d) 0.25

**Question 22:
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**Question 23:
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**Question 24:
**A bullet is shot from a rifle. As a result the rifle recoils. The kinetic energy of rifle as compared to that of bullet is

(a) less

(b) greater

(c) equal

(d) cannot be concluded

**Question 25:
**Two bodies of masses m1, and m2 and having velocities v1 and v2 respectively, moving along a straight line are brought to rest by equal resistance forces. If one moves twice as that of the duration of other but goes only 1/2 of the distance covered by the other before coming to rest, the ratio v1/v2 and m1/m2 are

(a) 1/4,8

(b) 1/2,1/4

(c) 1/8,1/2

(d) 1/4,1/6

**Question 26:
**The angle between the two vectors A = 3i + 4j + 5k andB = 3i + 4j-5k will be

(a) 90°

(b) 0°

(c) 60°

(d) 45°

**Question 27:
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**Question 28:
**A force acts on a 3.0 g particle in such a way that the position of the particles as a function of time is given by x = 3t – 4t

^{2}+t

^{3}, where x is in metre and t is in second. The work done during the first 4 s is

(a) 570 mJ

(b) 450 mJ

(c) 490 mJ

(d) 530 mJ

**Question 29:
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**Question 30:
**A flywheel rotating about a fixed axis has a kinetic energy of 360 J when its angular speed is 30 rads

^{-1}. The moment of inertia of the flywheel about the axis of rotation is

(a) 0.15 kg-m

^{2}

(b) 0.75 kg-m

^{2}

(c) 0.60kg-m

^{2}

(d) 0.80kg-m

^{2}

**Question 31:
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**Question 32:
**A tube of length L is filled completely with an incompressible liquid of mass M and closed at both the ends. The tube is then rotated in a horizontal plane about one of its ends with a uniform angular velocity to . The force exerted by the liquid at the other end is

(a) Mω

^{2}L/2

(b) Mω

^{2}L

(c) Mω

^{2}L/4

(d) Mω

^{2}L

^{2}/2

**Question 33:
**Two racing cars of masses m1 and m2 are moving in circles of radii r1 and r2 respectively. Their speeds are such that each makes a complete circle in the same time t.The ratio of the angular speeds of the first to the second car is

(a) 1:1

(b) m1: m2

(c) r1: r2

(d) m1m2 : r1r2

**Question 34:
**A wheel is rotating at 900 rpm about its axis. When the power is cut-off it comes to rest in 1 min. The angular retardation in rad s

^{-2}is

(a) ∏/2

(b) ∏/4

(C) ∏/6

(d) ∏/8

**Question 35:
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**Question 36:
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**Question 37:
**Two bodies of mass 10 kg and 5 kg moving in concentric orbits of radius R and r such that their periods are the same. Then, the ratio between their centripetal acceleration is

(a) R/r

(b) r/R

(c) R

^{2}/r

^{2}

(d) r

^{2}/R

^{2}

**Question 38:
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**Question 39:
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**Question 40:
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**Question 41:
**The moon’s radius is 1/4 that of the earth and its mass is 1/80 times that of the earth. If g represents the acceleration due to gravity on the surface of the earth, then on the surface of the moon its value is

(a) g

_{e}/4

(b) g

_{e}/5

(c) g

_{e}/6

(d) g

_{e}/8

**Question 42:
**A circular road of radius 1000 m has banking angle 45°. The maximum safe speed of a car having mass 200 kg will be, if the coefficient of friction between tyre and road is 0.5.

(a) 172 ms

^{-1}

(b) 124 ms

^{-1}

(c) 99ms

^{-1}

(d) 86ms

^{-1}

**Question 43:
**A body of mass m hangs at one end of a string of length l the other end of which is fixed. It is given a horizontal velocity, so that the string would just reach where it makes an angle of 60° with the vertical. The tension in the string at bottom most point position is

(a) 2mg

(b) mg

(c) 3mg

(d) √3 mg

**Question 44:
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**Question 45:
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**Question 46:
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**Question 47:
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**Question 48:
**If the angular momentum of any rotating body increases by 200%, then the increase in its kinetic energy

(a) 400%

(b) 800%

(c) 200%

(d) 100%

**Question 49:
**A body is rolling down an inclined plane. If KE of rotation is 40% of KE in translatory state, then the body is a

(a) ring

(b) cylinder

(c) hollow ball

(d) solid ball

**Question 50:
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**Question 51:
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### Answers:

### Hints And Solutions: