Classes of Levers
ANSWER :
Class 1,
Class 2,
Class 3
Class 1 Levers
ANSWER :
Fulcrum is in the middle, with the effort (input) force on one side of the fulcrum and re-
sistance (output) on the other side
.Mechanical Advantage greater or less than 1
Ex: Seesaw, Crowbar, Pair of Scissors.
Class 2 Levers
ANSWER :
Resistance is in the middle, the effort is applied on one side of the resistance and the ful-
crum on the other side
.Mechanical Advantage is always greater than 1
Ex: Wheelbarrow, nutcracker, bottle opener, or the brake pedal of a car.
Class 3 Levers
ANSWER :
Effort in the middle, the resistance is on one side of the effort and the fulcrum is located on
the other side.
1
,Mechanical Advantage is always less than 1
Ex: Pair of tweezers, human mandible
Lever Definitions
ANSWER :
Lever machine consisting of a beam or rigid rod pivoted at a fixed hinged, or fulcrum.
Input Force = Effort
Output Force = Load or Resistance
What does "fre, 123" mean?
ANSWER :
Fulcrum is in the middle for Class 1 LeversResistance (output) in middle for Class 2Effort (in-
put) in the middle for Class 3
Overall Test Overview:
ANSWER :
1) 30-minute period to read 2 essays- 2-hour time limit begins to answer (100 questions).
2) Watch 2 short videos and answer (20 questions) based on the scenarios.
3) Apply mechanical reasoning (25 questions, i.e. Fluid Dynamics, levers, belt and pulleys,
gears)
4) Mathematical Problems (20 questions, i.e. addition, division, angles, area, volume, deci-
mals, ratios, percentages)
5) Recall and Comprehend Technical Information (35 questions, recall from first two essays,
in addition to one or two more at this time)
Formula for Determining the head pressure difference between an intake and output
ANSWER :
1 vertical foot = 0.433 psi
1 psi = 2.31 vertical feet
2
, Be mindful of questions with absolutes. What are some absolutes and why watch out for
them?
ANSWER :
Examples of absolutes are "absolutely, always, forever, completely, infinite, never, only, sole,
undeniable, or wholly".Absolutes or any sort of broad statements should be suspected as
wrong.
Recall and Comprehend Technical Information
ANSWER :
- Read one to four essays
-35 questions total (including questions for essays in back of the test booklet)
- notes can be written on the essay packet, NOT any other testing material.
- 15 - 20 questions from these essays were handed out in the first 30 minutes.
Gear Train, or commonly called "Transmission"
ANSWER :
Two or more gears working in a sequence, producing mechanical advantage through a gear
ratio.
Relationship between Speed, Torque, and Power:
ANSWER :
Power = 2pi x Speed (w) x Torque (nm)/ 60
Torque = 60 x Power (kW)/2pi x Speed (Rpm)
Belt and Pulley Systems
ANSWER :
3
ANSWER :
Class 1,
Class 2,
Class 3
Class 1 Levers
ANSWER :
Fulcrum is in the middle, with the effort (input) force on one side of the fulcrum and re-
sistance (output) on the other side
.Mechanical Advantage greater or less than 1
Ex: Seesaw, Crowbar, Pair of Scissors.
Class 2 Levers
ANSWER :
Resistance is in the middle, the effort is applied on one side of the resistance and the ful-
crum on the other side
.Mechanical Advantage is always greater than 1
Ex: Wheelbarrow, nutcracker, bottle opener, or the brake pedal of a car.
Class 3 Levers
ANSWER :
Effort in the middle, the resistance is on one side of the effort and the fulcrum is located on
the other side.
1
,Mechanical Advantage is always less than 1
Ex: Pair of tweezers, human mandible
Lever Definitions
ANSWER :
Lever machine consisting of a beam or rigid rod pivoted at a fixed hinged, or fulcrum.
Input Force = Effort
Output Force = Load or Resistance
What does "fre, 123" mean?
ANSWER :
Fulcrum is in the middle for Class 1 LeversResistance (output) in middle for Class 2Effort (in-
put) in the middle for Class 3
Overall Test Overview:
ANSWER :
1) 30-minute period to read 2 essays- 2-hour time limit begins to answer (100 questions).
2) Watch 2 short videos and answer (20 questions) based on the scenarios.
3) Apply mechanical reasoning (25 questions, i.e. Fluid Dynamics, levers, belt and pulleys,
gears)
4) Mathematical Problems (20 questions, i.e. addition, division, angles, area, volume, deci-
mals, ratios, percentages)
5) Recall and Comprehend Technical Information (35 questions, recall from first two essays,
in addition to one or two more at this time)
Formula for Determining the head pressure difference between an intake and output
ANSWER :
1 vertical foot = 0.433 psi
1 psi = 2.31 vertical feet
2
, Be mindful of questions with absolutes. What are some absolutes and why watch out for
them?
ANSWER :
Examples of absolutes are "absolutely, always, forever, completely, infinite, never, only, sole,
undeniable, or wholly".Absolutes or any sort of broad statements should be suspected as
wrong.
Recall and Comprehend Technical Information
ANSWER :
- Read one to four essays
-35 questions total (including questions for essays in back of the test booklet)
- notes can be written on the essay packet, NOT any other testing material.
- 15 - 20 questions from these essays were handed out in the first 30 minutes.
Gear Train, or commonly called "Transmission"
ANSWER :
Two or more gears working in a sequence, producing mechanical advantage through a gear
ratio.
Relationship between Speed, Torque, and Power:
ANSWER :
Power = 2pi x Speed (w) x Torque (nm)/ 60
Torque = 60 x Power (kW)/2pi x Speed (Rpm)
Belt and Pulley Systems
ANSWER :
3
