Electricity and Magnetism

A balloon is rubbed all over with wool.  The balloon will now attract wool because the balloon and wool

• are magnets
• have opposite charges
• have like charges
• have neutral charges

In a static discharge, which particles move from one object to another?

• protons
• neutrons
• electrons
• atoms

Which of the following could be used as the core of a simple electromagnet?

• drinking straw
• iron nail 
• a soda bottle
• an ink pen

A piece of nickel will be attracted to

• only the north pole of an electromagnet
• only the south pole of an electromagnet
• either pole of an electromagnet
• the iron core of an electromagnet

What is voltage?

• a measure of electric current
• a kind of static elecricity
• a kind of current electricity
• a measure of potential energy difference

Which of these in an insulator?

• a copper wire
• a silver spoon
• a plastic coating on a wire
• an aluminum coating on a wire

What is the purpose of a switch in an electric circuit?

• to allow the circuit to be opened or closed
• to change the direction of the current
• to provide a push for the current
• to increase the electric power to the load

What is the purpose of an electric motor?

• to convert electrical energy to mechanical energy
• to convert chemical energy to electrical energy
• to convert mechanical energy to electrical energy
• to convert mechanical energy to heat energy

Which of these is NOT a function of a diode?

• to turn current on
• to turn current off
• to block the flow of current in the wrong direction
• to adjust the amount of current that flows

Electric current flowing through a wire produces

• static electricity
• an open circuit
• a permanent magnet
• a magnetic field