Mechanical Aptitude Test Principles 1 — Questions and Answers
Question 1: Newton's Third Law of Motion states that for every action there is:
- An equal force in the same direction
- An equal and opposite reaction (Correct answer)
- A proportional increase in velocity
- A reduction in friction
Correct answer: An equal and opposite reaction
Newton's Third Law states that forces always occur in pairs — when object A exerts a force on object B, object B exerts an equal force in the opposite direction on object A.
Question 2: Pascal's Principle states that pressure applied to an enclosed fluid is:
- Absorbed by the container walls
- Transmitted unequally based on depth
- Transmitted equally in all directions throughout the fluid (Correct answer)
- Lost as heat energy
Correct answer: Transmitted equally in all directions throughout the fluid
Pascal's Principle is the basis of hydraulic systems — any pressure applied to a confined fluid is transmitted equally and undiminished to every point in the fluid.
Question 3: According to Archimedes' Principle, the buoyant force acting on a submerged object equals:
- The weight of the object itself
- The weight of the fluid displaced by the object (Correct answer)
- The volume of the object times atmospheric pressure
- The density of the fluid times the object's weight
Correct answer: The weight of the fluid displaced by the object
Archimedes' Principle states that the upward buoyant force on an object equals the weight of the fluid it displaces, which determines whether the object floats or sinks.
Question 4: Bernoulli's Principle states that as the speed of a fluid increases, its pressure:
- Increases proportionally
- Remains constant
- Decreases (Correct answer)
- Doubles
Correct answer: Decreases
Bernoulli's Principle describes the inverse relationship between fluid speed and pressure — faster-moving fluid exerts less lateral pressure, which is why aircraft wings generate lift.
Question 5: The mechanical advantage of a simple machine is defined as the ratio of:
- Work output to work input
- Output force to input force (Correct answer)
- Input distance to output force
- Speed gained to effort applied
Correct answer: Output force to input force
Mechanical advantage (MA) = Output Force ÷ Input Force. A MA greater than 1 means the machine multiplies force, allowing a smaller effort to move a larger load.
Question 6: The Law of Conservation of Momentum states that in a closed system with no external forces, the total momentum:
- Gradually decreases due to friction
- Increases as objects speed up
- Is converted to kinetic energy
- Remains constant before and after a collision (Correct answer)
Correct answer: Remains constant before and after a collision
Conservation of momentum means the total momentum of all objects in a closed system stays the same — momentum lost by one object is gained by another, as seen in billiard ball collisions.
Mechanical Aptitude Test Principles 1
Newton's Third Law of Motion states that for every action there is: