Principles Questions and Answers Flashcards
6 cards from real MECHANICAL APTITUDE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Principles Questions and Answers flashcards as text
What is the principle of conservation of energy?
Answer: Energy cannot be created or destroyed, only transformed
The law of conservation of energy states that energy cannot be created or destroyed — it can only be transformed from one form to another. The total energy in a closed system remains constant.
What is Hooke's Law?
Answer: The extension of a spring is proportional to the applied force
Hooke's Law states that the deformation (extension or compression) of an elastic material is directly proportional to the force applied, within the elastic limit: F = kx, where k is the spring constant and x is the deformation.
What does the principle of moments state?
Answer: For a body in rotational equilibrium, the sum of clockwise moments equals the sum of counterclockwise moments
The principle of moments states that for a system in rotational equilibrium, the total clockwise moments about any point equal the total counterclockwise moments. A moment is force multiplied by perpendicular distance from the pivot.
What is the efficiency of a machine that outputs 750J of useful work from 1000J of input energy?
Answer: 75%
Efficiency = (useful output / total input) × 100% = (750/1000) × 100% = 75%. The remaining 25% (250J) is lost to friction, heat, sound, or other non-useful energy forms.
What does Pascal's principle state about pressure in a confined fluid?
Answer: Pressure applied to a confined fluid is transmitted equally in all directions
Pascal's principle states that pressure applied to an enclosed, incompressible fluid is transmitted undiminished and equally to every point in the fluid and to the walls of its container. This is the foundation of all hydraulic systems.
The mechanical advantage of an inclined plane is calculated by dividing what?
Answer: Length of the slope by the height
The ideal mechanical advantage of an inclined plane equals the length of the slope divided by the vertical height: IMA = L/h. A longer, more gradual slope provides greater mechanical advantage, requiring less force to move an object upward.