4th Class Power Engineering Part A Exam Accurate 100%

VR - ANSWER Equal to R/r and D/d Load /Effort - ANSWER Equal to R/r Scalar - ANSWER A physical quantity that has magnitude but no direction Vector - ANSWER A quantity that has magnitude and direction Space Diagram - ANSWER Illustrates a system of vectors Co-planar Vectors - ANSWER Vectors that are all in the same plane Concurrent Vectors - ANSWER Vectors whose lines of action meet at one point Resultant - ANSWER A vector that represents the sum of two or more vectors Absolute Pressure - ANSWER Atmospheric pressure + gauge pressure Static Friction - ANSWER A friction force that acts on objects that are not moving. Always greater than kinetic friction Kinetic Friction - ANSWER Friction that opposes motion once the motion has already started. Not affected by speed of body Always greater than rolling friction. Rolling Friction - ANSWER The friction force that acts on rolling objects, Always less than kinetic friction Fluid Friction - ANSWER Friction that occurs as an object moves through a fluid Force of Friction - ANSWER Force that resists motion when two materials are in contact. Proportional to the force that presses the two surfaces together. Not affected by area. Affected by roughness. Elasticity - ANSWER The ability of a material to return to its original shape after being disturbed Stiffness - ANSWER Ability of a material to resist a change in shape or size when a load is applied Plasticity - ANSWER Ability of a material to r