1. Which of the following is NOT correct about an inelastic collision?

[A] Linear momentum is conserved

[B] Kinetic energy is conserved

[C] Total energy is conserved

[D] Some or all the forces involved may be non-conservative in nature

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**Correct Answer:** B [Kinetic energy is conserved]

2. The dot product of two vectors A and B is equal to the product of magnitude of A and B and __________?

[A] cosine of the largest angle between them

[B] sine of the largest angle between them

[C] cosine of the smallest angle between them

[D] sine of the smallest angle between them

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**Correct Answer:** C [cosine of the smallest angle between them]

3. What is the dot product of two perpendicular vectors?

[A] 1

[B] 0

[C] -1

[D] 1/2

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4. Work done is defined as the dot product of which of the following vectors?

[A] Force and acceleration

[B] Force and area

[C] Force and instantaneous velocity

[D] Force and displacement

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**Correct Answer:** D [Force and displacement]

5. What is the dimensional formula of work done?

[A] M^{1} L^{1} T^{-1}

[B] M^{1} L^{2} T^{-1}

[C] M^{1} L^{-1} T^{-2}

[D] M^{1} L^{2} T^{-2}

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**Correct Answer:** D [M^{1} L^{2} T^{-2}]

6. Which of the following is NOT correct about units of work:

[A] 1 joule = 10^{7} ergs

[B] 1 kg-m = 1 joule

[C] 1 kg-m = 9.8 joule

[D] 1 joule = 1 Nm

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**Correct Answer:** B [1 kg-m = 1 joule]

7. Work done will NOT be zero in which of the following case/cases?

[A] When displacement is zero

[B] When angle between force and displacement vector is zero

[C] When angle between force and displacement vector is 90°

[D] When force is zero

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**Correct Answer:** B [When angle between force and displacement vector is zero]

8. The work done by a variable force is given by:

[A] area under the force curve and the displacement axis

[B] square of the area under the force curve and the displacement axis

[C] natural log of the area under the force curve and the displacement axis

[D] twice the area under the force curve and the displacement axis

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**Correct Answer:** A [area under the force curve and the displacement axis]

9. Which of the following is NOT a conservative force?

[A] Electrostatic force

[B] Magnetic force

[C] Force in an elastic spring

[D] Frictional force

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**Correct Answer:** D [Frictional force]

10. The work done in moving a body over a smooth inclined plane does not depend on which of the following?

[A] mass of the body

[B] height of the inclined plane

[C] slope of the inclined plane

[D] All of the above

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**Correct Answer:** C [slope of the inclined plane]