EEI Tech Mechanical Concept Flashcards

A first-class lever has the effort 4 ft from the fulcrum and the load 1 ft from the fulcrum. What is its mechanical advantage?

Answer: 4

Mechanical advantage equals effort arm divided by load arm: 4/1 = 4.

Which gear arrangement allows a driver and driven shaft to rotate in the SAME direction using gears alone?

Answer: Two gears with an idler gear between them

An idler gear placed between two gears reverses direction twice, keeping driver and driven turning the same way.

On a screw, the distance the screw advances in one full turn is called the:

Answer: Pitch

Pitch is the linear distance traveled per complete revolution of the screw.

A 200 lb load sits on a frictionless inclined plane 10 ft long with a vertical rise of 2 ft. What is the ideal mechanical advantage?

Answer: 5

Ideal mechanical advantage equals length divided by height: 10/2 = 5.

Which of the following best describes torque?

Answer: A rotational force that tends to cause rotation

Torque is the turning effect produced by a force acting at a distance from a pivot.

Water flows through a pipe that narrows from a wide section to a narrow section. In the narrow section the water:

Answer: Flows faster

By continuity, the same volume must pass through a smaller area, so velocity increases.

A flywheel is used in machines primarily to:

Answer: Store rotational energy and smooth out speed variations

A flywheel's inertia stores energy and keeps rotational speed steady between power strokes.