Principles of Engineering (P.O.E) Final Exam
Review Questions with Certified Solutions
Energy - Answer the ability to do work
Nonrenewable energy - Answer energy not able to be replaced ex: fossil fuels, oil, gas
Renewable energy - Answer replaceable energy ex: food, animals
Inexhaustible energy - Answer never stops producing energy ex: wind, hydrualic, solar
Work - Answer The force applied on an object times
distance the object travels parallel to the
force
Formula for Work - Answer Force x Distance
6 Simple machines - Answer wedge, screw, inclined plane, wheel and axle, lever, and pulley
Wedges - Answer Tapers to a thin edge and is used for splitting,
raising heavy bodies, or for tightening by being
driven into something ex: axe
Inclined Planes - Answer Ex: slide, ramp, rollercoaster
Screws - Answer An inclined plane wrapped around a cylinder, forming the path and pitch. A wheel and
axle used to create rotary motion. Generally high MA. Large friction loss.
, Wheels and Axles - Answer A wheel is a lever arm fixed to a shaft, called an axle. The wheel and axle
move together as a simple lever to lift or move an item by rolling. It is important to know which is
applying the effort and resistance force - wheel or axle.
Wheel and Axle IMA - Answer Diameter of effort (wheel or axle) / Diameter of resistance (wheel or axle)
Levers - Answer A rigid bar used to exert a pressure or sustain a weight at one point of its length by the
application of a force at a second point and turning on a fulcrum at a third.There are three classes: first,
second, and third class.
1st Class Lever - Answer Fulcrum is located between the effort and the resistance forces. Effort and
resistance forces are applied to the lever arm in the same direction. Only class of lever that can have an
MA greater than or less than 1.
2nd Class Lever - Answer Fulcrum is located at one end of the lever. Resistance force is located between
the fulcrum and the effort force. Resistance force and effort force are in opposing directions. Always has
a mechanical advantage >1.
3rd Class Lever - Answer Fulcrum is located at one end of the lever.Effort force is located between the
fulcrum and the resistance. Resistance force and effort force are in opposing
directions. Always has a mechanical advantage < 1.
Moment - Answer turning effect of a force about a point
equal to the magnitude of the force multiplied by the distance
Formula for Moment - Answer Distance x Force (d x F)
Rotational Equilibrium - Answer When the sum of all of the moments on a lever equals 0
Formula for Rotational Equilibrium - Answer Effort Moment (cc wise) = Resistance Moment (clockwise)
Torque - Answer A force that produces or tends to produce rotation or torsion.
Review Questions with Certified Solutions
Energy - Answer the ability to do work
Nonrenewable energy - Answer energy not able to be replaced ex: fossil fuels, oil, gas
Renewable energy - Answer replaceable energy ex: food, animals
Inexhaustible energy - Answer never stops producing energy ex: wind, hydrualic, solar
Work - Answer The force applied on an object times
distance the object travels parallel to the
force
Formula for Work - Answer Force x Distance
6 Simple machines - Answer wedge, screw, inclined plane, wheel and axle, lever, and pulley
Wedges - Answer Tapers to a thin edge and is used for splitting,
raising heavy bodies, or for tightening by being
driven into something ex: axe
Inclined Planes - Answer Ex: slide, ramp, rollercoaster
Screws - Answer An inclined plane wrapped around a cylinder, forming the path and pitch. A wheel and
axle used to create rotary motion. Generally high MA. Large friction loss.
, Wheels and Axles - Answer A wheel is a lever arm fixed to a shaft, called an axle. The wheel and axle
move together as a simple lever to lift or move an item by rolling. It is important to know which is
applying the effort and resistance force - wheel or axle.
Wheel and Axle IMA - Answer Diameter of effort (wheel or axle) / Diameter of resistance (wheel or axle)
Levers - Answer A rigid bar used to exert a pressure or sustain a weight at one point of its length by the
application of a force at a second point and turning on a fulcrum at a third.There are three classes: first,
second, and third class.
1st Class Lever - Answer Fulcrum is located between the effort and the resistance forces. Effort and
resistance forces are applied to the lever arm in the same direction. Only class of lever that can have an
MA greater than or less than 1.
2nd Class Lever - Answer Fulcrum is located at one end of the lever. Resistance force is located between
the fulcrum and the effort force. Resistance force and effort force are in opposing directions. Always has
a mechanical advantage >1.
3rd Class Lever - Answer Fulcrum is located at one end of the lever.Effort force is located between the
fulcrum and the resistance. Resistance force and effort force are in opposing
directions. Always has a mechanical advantage < 1.
Moment - Answer turning effect of a force about a point
equal to the magnitude of the force multiplied by the distance
Formula for Moment - Answer Distance x Force (d x F)
Rotational Equilibrium - Answer When the sum of all of the moments on a lever equals 0
Formula for Rotational Equilibrium - Answer Effort Moment (cc wise) = Resistance Moment (clockwise)
Torque - Answer A force that produces or tends to produce rotation or torsion.
