Engineering Mechanics (Statics and Dynamics) MCQs

Which of the following is a scalar quantity in mechanics? A. Force B. Velocity C. Acceleration D. Mass Answer: D The resultant of two forces acting at a point is maximum when the angle between them is: A. 0 degrees B. 45 degrees C. 90 degrees D. 180 degrees Answer: C If three forces acting at a point are in equilibrium, they must be: A. Coplanar and concurrent B. Parallel C. Equal in magnitude D. Perpendicular Answer: A The moment of a force about a point is: A. Force multiplied by distance B. Force divided by distance C. Force multiplied by velocity D. Force multiplied by time Answer: A When a body is in equilibrium under the action of several forces, then: A. The algebraic sum of the forces is zero B. The algebraic sum of the moments about any point is zero C. Both A and B D. None of these Answer: C The condition of equilibrium for concurrent forces is that the algebraic sum of the forces should be: A. Zero B. Negative C. Positive D. None of these Answer: A The property of a body to remain at rest or to remain in uniform motion along a straight line is called: A. Inertia B. Velocity C. Force D. Momentum Answer: A The minimum number of coplanar concurrent forces required to keep a rigid body in equilibrium is: A. 1 B. 2 C. 3 D. 4 Answer: 1 If a force of 10 N acts at a distance of 5 m from the pivot, the moment of the force about the pivot is: A. 15 Nm B. 10 Nm C. 5 Nm D. 2 Nm Answer: B Two forces of 6 N and 8 N are acting at an angle of 60 degrees to each other. The magnitude of their resultant is: A. 10 N B. 11 N C. 12 N D. 14 N Answer: A Dynamics Dynamics deals with: A. Bodies in equilibrium B. Bodies in motion C. Bodies at rest D. None of these Answer: B The force acting on a body moving in a circular path is: A. Centripetal force B. Centrifugal force C. Gravitational force D. Normal force Answer: A The term ‘momentum’ is defined as the: A. Force acting on a body B. Product of mass and velocity C. Force acting in the opposite direction of motion D. None of these Answer: B The force that opposes the relative motion between two surfaces in contact is called: A. Friction B. Gravity C. Tension D. Normal force Answer: A Newton’s second law of motion states that: A. An object at rest will remain at rest B. The acceleration of an object is directly proportional to the net force acting on it C. For every action, there is an equal and opposite reaction D. The gravitational force between two objects is directly proportional to the product of their masses Answer: B The unit of momentum is the same as that of: A. Force B. Energy C. Power D. Velocity Answer: A Which of the following is a scalar quantity? A. Force B. Velocity C. Momentum D. Acceleration Answer: B The weight of a body is a force which acts: A. Perpendicularly downward B. Perpendicularly upward C. Horizontally D. None of these Answer: A The force acting on a body falling freely due to gravity is called: A. Tension B. Friction C. Weight D. None of these Answer: C The motion of a projectile is: A. Linear B. Curvilinear C. Circular D. None of these Answer: B Mixed Which of the following is not a vector quantity? A. Displacement B. Acceleration C. Force D. Speed Answer: D Which of the following is not a unit of force? A. Newton B. Dyne C. Pascal D. Kilogram-force Answer: C The SI unit of work done is: A. Joule B. Watt C. Newton D. Pascal Answer: A The coefficient of restitution is defined as the ratio of: A. Initial velocity to final velocity B. Final velocity to initial velocity C. Initial relative velocity to final relative velocity D. Final relative velocity to initial relative velocity Answer: D The law which states that the total momentum of a system of particles remains constant if no external force acts on the system is called: A. Newton’s first law of motion B. Newton’s second law of motion C. Newton’s third law of motion D. Law of conservation of momentum Answer: D The velocity of a body is a: A. Vector quantity B. Scalar quantity C. Both A and B D. None of these Answer: A The SI unit of velocity is: A. Meter B. Meter per second C. Second D. None of these Answer: B The law that states that the internal forces between the particles of a system do not change the total momentum of the system is known as: A. Newton’s first law of motion B. Newton’s second law of motion C. Newton’s third law of motion D. Law of conservation of momentum Answer: D Which of the following is not a type of friction? A. Static friction B. Kinetic friction C. Rolling friction D. Gravitational friction Answer: D The property of a body to resist any change in its state of motion is called: A. Inertia B. Momentum C. Force D. Weight Answer: A Dynamics (Continued) The time rate of change of momentum of a body is equal to the: A. Force acting on it B. Acceleration produced in it C. Power developed D. Weight Answer: A The ratio of the work done to the energy expended is called: A. Efficiency B. Friction C. Power D. None of these Answer: A The velocity ratio of a machine is 5. Its mechanical advantage is: A. 2 B. 5 C. 10 D. None of these Answer: B A weight lifter lifts a weight of 200 N to a height of 2 m in 2 s. The power expended is: A. 200 W B. 400 W C. 800 W D. 1000 W Answer: A The angle between the applied force and the displacement in work done is: A. 0 degrees B. 30 degrees C. 60 degrees D. 90 degrees Answer: D The resistance offered by the body to any change in its state of rest or of uniform motion is called: A. Inertia B. Acceleration C. Force D. Power Answer: A The total force exerted on the body is called: A. Impulse B. Momentum C. Action D. None of these Answer: B The tendency of a body to resist any change in its state of motion is due to: A. Inertia B. Force C. Power D. Momentum Answer: A The force that tends to pull all bodies towards the center of the earth is called: A. Magnetic force B. Gravitational force C. Centrifugal force D. Centripetal force Answer: BThe formula F = ma is used to measure: A. Acceleration B. Momentum C. Force D. Power Answer: C The force acting on a body due to gravity is called: A. Weight B. Mass C. Volume D. Density Answer: A The principle of conservation of energy states that: A. Energy can neither be created nor destroyed B. Energy is always created in any process C. Energy can be created but not destroyed D. Energy is always destroyed in any process Answer: A The unit of power is: A. Joule B. Watt C. Newton D. Pascal Answer: B The SI unit of momentum is: A. Kg m/s B. Kg m C. N m/s D. N s Answer: A A force of 5 N acts on a body of mass 2 kg for 10 seconds. The change in momentum of the body is: A. 10 kg m/s B. 25 kg m/s C. 50 kg m/s D. 100 kg m/s Answer: B The mechanical advantage of a machine is 4. It implies that: A. The machine increases the force by a factor of 4 B. The machine increases the distance moved by a factor of 4 C. The machine increases the speed by a factor of 4 D. The machine decreases the force by a factor of 4 Answer: A Which of the following is not a unit of energy? A. Joule B. Watt-hour C. Newton D. Calorie Answer: C A car accelerates uniformly from rest to a speed of 18 m/s in 5 seconds. The acceleration of the car is: A. 2 m/s² B. 3.6 m/s² C. 5 m/s² D. 9 m/s² Answer: A If the force acting on a body remains constant, its acceleration is: A. Zero B. Constant C. Increasing D. Decreasing Answer: B The term ‘impulse’ is defined as the: A. Change in momentum B. Change in velocity C. Change in force D. Change in displacement Answer: A