POE Unit 1 Test Review

1.) How many classes of levers are there?

• 1

• 2

• 3

• 4

Which of the following is an example of a 2nd class lever?

• wheel barrow

• see saw

• fishing pole

• none of these are examples of a 2nd class lever

Which of the following is an example of a 3rd class lever?

• fishing pole

• wheel barrow

• see saw

• none of these

You can find the MA of a system by which of the following:

• Output distance divided by resistance force

• Output force divided by effort force

• input force divided by resistance force

• effort distance divided by input distance

A force of 20 lbs is applied to a 0.5-foot diameter wheel. The wheel is turning a ¼ inch diameter axle. How much mechanical advantage does the wheel provide?

• 2

• 24

• 480

• 48

If the input (driver) gear is 30 teeth and the output (driven) gear is 40 teeth, what is the gear ratio?

• 1.33

• 0.75

• 120

• 1.2

Find the mechanical advantage of a wheel and axle system if the wheel has a radius of 2.5 feet and the axle has a radius of 6 inches if the force is put on the axle.

• 0.2

• 0.42

• 2.4

• 5

The figure shows a belt driven system. Pulley B, which has a diameter of 9 inches, is being driven by pulley A, which has a diameter of 2 inches. If pulley A is spinning at 30 RPMs, then how fast is pulley B spinning?

• 6.7 RPMs

• 135 RPMs

• 2.7 RPMs

• 60 RPMs

Determine the current across R1.

• 0.003 A

• 3.33 A

• 0.003 mA

• 300 A

Determine the total current.

• 9A

• 0.015 mA

• 9 mA

• 15.15 mA