01: Engineering Mechanics Interview Questions for PSUs

1. What is Engineering Mechanics?
• Engineering Mechanics is the branch of science that deals with the behavior of objects under the action of forces.
2. What are the types of forces?
• The types of forces are contact forces and non-contact forces.
3. What is a free body diagram?
• A free body diagram is a diagram that shows all the forces acting on an object.
4. What is the difference between a scalar and a vector?
• A scalar is a quantity that has only magnitude, while a vector is a quantity that has both magnitude and direction.
5. What is Newton's first law of motion?
• Newton's first law of motion states that an object at rest will remain at rest, and an object in motion will remain in motion with a constant velocity, unless acted upon by an external force.
6. What is Newton's second law of motion?
• Newton's second law of motion states that the acceleration of an object is directly proportional to the net force acting on the object, and inversely proportional to its mass.
7. What is Newton's third law of motion?
• Newton's third law of motion states that for every action, there is an equal and opposite reaction.
8. What is the principle of conservation of energy?
• The principle of conservation of energy states that energy cannot be created or destroyed, only transferred or transformed from one form to another.
9. What is the principle of conservation of momentum?
• The principle of conservation of momentum states that the total momentum of a system of objects remains constant if no external forces act on the system.
10. What is the difference between work and power?
• Work is the product of force and displacement, while power is the rate at which work is done.
11. What is stress?
• Stress is the force per unit area acting on a material.
12. What is strain?
• Strain is the deformation per unit length of a material.
13. What is Hooke's law?
• Hooke's law states that the deformation of a material is directly proportional to the force applied to it, as long as the material remains within its elastic limit.
14. What is the difference between stress and strain?
• Stress is the force per unit area acting on a material, while strain is the deformation per unit length of a material.
15. What is the difference between static and dynamic equilibrium?
• Static equilibrium is when an object is at rest, while dynamic equilibrium is when an object is moving at a constant velocity.
16. What is the difference between a machine and a structure?
• A machine is a device that converts one form of energy to another, while a structure is a system of interconnected parts that supports a load.
17. What is the difference between a beam and a column?
• A beam is a horizontal or inclined structural member that supports a load, while a column is a vertical structural member that supports a load.
18. What is the difference between a truss and a frame?
• A truss is a structure composed of interconnected triangles, while a frame is a structure composed of interconnected rectangles.
19. What is the difference between a simple machine and a compound machine?
• A simple machine is a machine that has only one moving part, while a compound machine is a machine that has two or more simple machines working together.
20. What is the difference between a kinematic chain and a mechanism?
• A kinematic chain is a series of interconnected links that transmit motion, while a mechanism is a system of interconnected parts that transmit motion and force.