IBEW Mechanical Reasoning Principles 4

Question 1

A flywheel is used in machinery primarily to:

Accepted Answer

Store rotational energy and smooth out speed fluctuations

Answer

A flywheel's rotational inertia stores kinetic energy, damping speed variations between power strokes.

Question 2

A screw has 16 threads per inch. How far does a nut advance along the screw for each complete turn?

Accepted Answer

1/16 inch

Answer

Each full revolution advances the nut one thread pitch; pitch = 1 ÷ threads per inch = 1/16 in.

Question 3

Which type of bearing is best suited for handling both radial and axial (thrust) loads simultaneously?

Accepted Answer

Angular contact ball bearing

Answer

Angular contact ball bearings are specifically designed to carry combined radial and axial loads due to their angled contact geometry.

Question 4

A centrifugal pump will lose its prime when:

Accepted Answer

Air enters the suction side of the pump

Answer

Air introduced to the suction side breaks the liquid column, preventing the impeller from creating the pressure differential needed to move water.

Question 5

Heat travels through the copper wires in an electrical panel primarily by:

Accepted Answer

Conduction

Answer

Conduction is heat transfer through direct contact between molecules within a solid material like copper wire.

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