Engineering Mechanics QnA

 Engineering Mechanics QNA:

Q1. The friction experienced by a body, when in motion, is known as -

Ans: dynamic friction

Q2. Two balls of equal mass and of perfectly elastic material are lying on the floor. One of the ball with velocity v is made to struck the second ball. Both the balls after impact will move with a velocity -

Ans: v/2

Q3. The velocity ratio in case of an inclined plane inclined at angle θ to the horizontal and weight being pulled up the inclined plane by vertical effort is -

Ans: sin θ

Q4. The range of projectile on a downward inclined plane is  __________  the range on upward inclined plane for the same velocity of projection and angle of projection.

Ans: more than

Q5. The angle of inclination of a vehicle when moving along a circular path __________ upon its mass.

Ans: does not depend

Q6. A body of weight W is required to move up on rough inclined plane whose angle of inclination with the horizontal is α. The effort applied parallel to the plane is given by(where μ = tanφ = Coefficient of friction between the plane and the body.)

Ans: P = W (sinα + μcosα)

Q7. If the resultant of two equal forces has the same magnitude as either of the forces, then the angle between the two forces is -

Ans: 120°

Q8. A smooth cylinder lying on its convex surface remains in __________ equilibrium.

Ans: unstable

Q9. Moment of inertia of a circular section about an axis perpendicular to the section is -

Ans: πd⁴/32

Q10. The unit of angular acceleration is -

Ans: rad/s²

Q11. The unit of angular acceleration is -

Ans: Newton’s laws of motion

Q12. Which of the following is termed as an action of pull or push of a body at rest or motion?

Ans: Force

Q13. What is Kinematics?

Ans: Branch of dynamics which deals with the study of bodies under motion without considering forces

Q14. Which of the following is the condition for the three-force theorem in mechanics?

Ans: The force system should be in equilibrium, co-planar, concurrent, or parallel

Q15. The internal force in structures among the following is?

Ans: Compression force

Q16. Which of the following doesn’t affect frictional force?

Ans: Area of contact

Q17. Which element of the truss section is made to apply the method of sections in the free body diagram?

Ans: Any section can be used

Q18. The change in the moment is equal to which of the following?

Ans: Area under the shear diagram

Q19. In the journal bearings calculations, the moment is the cross product of which of the following two vectors?

Ans: Radius and Force vectors

Q20. The normal force exerted by the surface of the wedge is normal to the surface of the ________

Ans: Base of the body residing over it