Mechanical Aptitude Levers, Pulleys, and Gears Flashcards
7 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 7 Mechanical Aptitude Levers, Pulleys, and Gears flashcards as text
A block-and-tackle system uses 3 movable pulleys and 3 fixed pulleys. What is the approximate mechanical advantage?
Answer: 6
The mechanical advantage of a block-and-tackle equals the number of rope segments supporting the load, which is 6 in this configuration.
A crowbar being used to pry open a crate is what class of lever?
Answer: First class
A crowbar is a first-class lever: the fulcrum (edge of crate) is between the effort (your hands pushing down) and the load (lid being lifted).
Gear A has 12 teeth and rotates at 600 RPM. If Gear B meshes with Gear A and rotates at 200 RPM, how many teeth does Gear B have?
Answer: 36 teeth
Using the gear ratio formula: Teeth B = (RPM A × Teeth A) ÷ RPM B = (600 × 12) ÷ 200 = 36 teeth.
In a gear train, the gear that receives power from the engine is called the:
Answer: Driver gear
The driver gear (also called the input gear) is the one connected to the power source and initiates motion in the gear train.
What happens to torque when a small gear drives a larger gear?
Answer: Torque increases
When a small driver gear turns a larger driven gear, speed decreases but torque increases proportionally (ignoring friction losses).
A movable pulley is always attached to:
Answer: The load being lifted
A movable pulley travels with the load, allowing two rope segments to share the weight and halving the required effort.
Which statement correctly describes the trade-off when using a longer effort arm on a lever?
Answer: Less effort is needed, but the effort must move a greater distance
A longer effort arm reduces the force needed (higher MA) but requires the effort to travel a greater arc distance to move the load.