Physics Quiz on Machines and Motion

What is the main characteristic of an efficient machine?

• It is heavy and large

• It requires more input than output

• It has high energy loss

• It does more work with less effort

Which of the following correctly defines mechanical advantage (MA)?

• Effort divided by load

• Output force divided by input force

• Load divided by effort

• Input work divided by output work

A pulley system is used to lift a 120 N object using only 30 N of effort. What is its mechanical advantage?

• 2

• 4

• 6

• 8

Which of these would increase the efficiency of a machine?

• Adding more friction

• Using rough surfaces

• Using lubricants to reduce friction

• Using larger force than necessary

Which of the following is not a characteristic of an efficient machine?

• High mechanical advantage

• Minimal energy loss

• Complicated design

• Smooth force transfer

What type of motion is primarily used by gears in a compound machine?

• Translational

• Vibrational

• Rotational

• Linear

A compound machine is made up of:

• Several electrical components

• Two or more simple machines

• Only gears and pulleys

• One type of simple machine

If a machine produces 80 J of output work and requires 100 J of input work, what is its efficiency?

• 80%

• 100%

• 20%

• 125%

Why is it important to reduce friction in a machine?

• To make it heavier

• To decrease output

• To reduce efficiency

• To conserve energy and improve efficiency

Which of the following is an example of a compound machine?

• Inclined plane

• Screw

• Bicycle

• Lever