4th Class Power Engineering Part A Exam Questions With Complete Solutions
Velocity (m/s) - (ANSWER)Change in position / time
Acceleration (m/s^2) - (ANSWER)Change in velocity (m/s) / time (s)
Force (Newton) - (ANSWER)mass (kg) x acceleration (m/s^2) , any action on a body that tends to change
its size, shape, or its state of rest or motion
Force of Gravity - (ANSWER)mass (kg) x 9.81 m/s^2
Pressure (Pa) - (ANSWER)Force (N) / area (m^2)
Work (J) - (ANSWER)Force (N) x distance (m)
Power - (ANSWER)Work done / time , Rate of doing work
Potential Energy (J) - (ANSWER)mass x gravity x height , the ability of a body to do work due by virtue of
its position
Kinetic Energy (J) - (ANSWER)1/2 x mass x velocity^2 , The ability of a body to do work due to its motion
Energy (J) - (ANSWER)The capacity of a body to do work
Tonne - (ANSWER)1000 kilograms
Moment of Force (Nm) - (ANSWER)Force (N) x Distance (m) , A force, acting on a body at any distance
from a point on that body, will tend to produce rotation around that point
Clockwise Moments - (ANSWER)Equal to Counter-clockwise moments
,4th Class Power Engineering Part A Exam Questions With Complete Solutions
Upward Forces - (ANSWER)Equal to Downward forces
Actual Mechanical Advantage (Ma) - (ANSWER)Load (N) / Effort (N)
Velocity Ratio (VR) - (ANSWER)Distance moved by Effort / Distance moved by Load
Efficiency - (ANSWER)Output Work / Input Work
Output Work - (ANSWER)Load x Distance moved by load
Input Work - (ANSWER)Effort x Distance moved by effort , Equals Output work + Wasted work
Ideal Mechanical Advantage (MA) - (ANSWER)Equal to Velocity Ratio (VR)
Load x r - (ANSWER)Equal to Effort x R
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
,4th Class Power Engineering Part A Exam Questions With Complete Solutions
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 retain its deformed shape when a deforming force is
removed
Ductility - (ANSWER)Ability of a material to be stretched and reduced in cross section without breaking
Toughness - (ANSWER)Ability of a material to absorb energy before breaking
, 4th Class Power Engineering Part A Exam Questions With Complete Solutions
Hardness - (ANSWER)Ability of a material to resist penetration
Stress - (ANSWER)Internal resistance to an external load , Equal to Load (N) / Area (m^2)
Tensile Stress - (ANSWER)Forces that act at opposite ends of a bar and pull away from each other,
creating tension on the bar
Compressive Stress - (ANSWER)A stress due to a force pushing together on a body
Shear Stress - (ANSWER)Forces on a bar that act parallel to another but are not on the same plane
Ultimate Stress - (ANSWER)The stress at which fracture of the material occurs
Allowable Stress - (ANSWER)The greatest stress which a material is capable of developing without
permanent deformation remaining upon the complete release of stress.
Elastic Limit - (ANSWER)Maximum stress that a material will withstand without permanent deformation.
Will return to its original size and shape
Factor of Safety - (ANSWER)Ultimate Stress / Allowable Stress
Strain - (ANSWER)A measure of the deformation produced in a member by a load , Equal to Change in
Length (l) / Original Length (L)
Circumferance - (ANSWER)pi x Diameter
Linear Speed - (ANSWER)Equal to rev/min x pi D / 60
Velocity (m/s) - (ANSWER)Change in position / time
Acceleration (m/s^2) - (ANSWER)Change in velocity (m/s) / time (s)
Force (Newton) - (ANSWER)mass (kg) x acceleration (m/s^2) , any action on a body that tends to change
its size, shape, or its state of rest or motion
Force of Gravity - (ANSWER)mass (kg) x 9.81 m/s^2
Pressure (Pa) - (ANSWER)Force (N) / area (m^2)
Work (J) - (ANSWER)Force (N) x distance (m)
Power - (ANSWER)Work done / time , Rate of doing work
Potential Energy (J) - (ANSWER)mass x gravity x height , the ability of a body to do work due by virtue of
its position
Kinetic Energy (J) - (ANSWER)1/2 x mass x velocity^2 , The ability of a body to do work due to its motion
Energy (J) - (ANSWER)The capacity of a body to do work
Tonne - (ANSWER)1000 kilograms
Moment of Force (Nm) - (ANSWER)Force (N) x Distance (m) , A force, acting on a body at any distance
from a point on that body, will tend to produce rotation around that point
Clockwise Moments - (ANSWER)Equal to Counter-clockwise moments
,4th Class Power Engineering Part A Exam Questions With Complete Solutions
Upward Forces - (ANSWER)Equal to Downward forces
Actual Mechanical Advantage (Ma) - (ANSWER)Load (N) / Effort (N)
Velocity Ratio (VR) - (ANSWER)Distance moved by Effort / Distance moved by Load
Efficiency - (ANSWER)Output Work / Input Work
Output Work - (ANSWER)Load x Distance moved by load
Input Work - (ANSWER)Effort x Distance moved by effort , Equals Output work + Wasted work
Ideal Mechanical Advantage (MA) - (ANSWER)Equal to Velocity Ratio (VR)
Load x r - (ANSWER)Equal to Effort x R
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
,4th Class Power Engineering Part A Exam Questions With Complete Solutions
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 retain its deformed shape when a deforming force is
removed
Ductility - (ANSWER)Ability of a material to be stretched and reduced in cross section without breaking
Toughness - (ANSWER)Ability of a material to absorb energy before breaking
, 4th Class Power Engineering Part A Exam Questions With Complete Solutions
Hardness - (ANSWER)Ability of a material to resist penetration
Stress - (ANSWER)Internal resistance to an external load , Equal to Load (N) / Area (m^2)
Tensile Stress - (ANSWER)Forces that act at opposite ends of a bar and pull away from each other,
creating tension on the bar
Compressive Stress - (ANSWER)A stress due to a force pushing together on a body
Shear Stress - (ANSWER)Forces on a bar that act parallel to another but are not on the same plane
Ultimate Stress - (ANSWER)The stress at which fracture of the material occurs
Allowable Stress - (ANSWER)The greatest stress which a material is capable of developing without
permanent deformation remaining upon the complete release of stress.
Elastic Limit - (ANSWER)Maximum stress that a material will withstand without permanent deformation.
Will return to its original size and shape
Factor of Safety - (ANSWER)Ultimate Stress / Allowable Stress
Strain - (ANSWER)A measure of the deformation produced in a member by a load , Equal to Change in
Length (l) / Original Length (L)
Circumferance - (ANSWER)pi x Diameter
Linear Speed - (ANSWER)Equal to rev/min x pi D / 60
