Science Chapter 2 - Electricity & Magnetism

Why is copper classified as a conductor?

• Electric current travels easily through copper.
• Copper may gain or lose electric charges.
• Copper resists the flow of electrical current.
• None of the other answer choices

Why are the wires in electric circuits often coated with plastic?

• The plastic carries the electric current.
• The plastic keeps the electric current inside the wire.  
• The plastic allows the wire to bend into different shapes.
• The plastic acts as a switch to turn the electric current on or off.  

Which set of materials could be used to make an electromagnet?

• A D-cell battery, a box of paper clips, and a switch
• A bar magnet, a copper wire, and a light bulb
• A bar magnet, a spool of electrical wire, and an electrical outlet
• An iron nail, a spool of electrical wire, and a D-cell battery

What parts make up a typical electric circuit?

• A battery, nail, switch, and wire
• An energy source, magnet, switch, and wire
• An energy source, resistor, switch, and wire
• None of the other answer choices

An electromagnet would be most useful for which of these tasks?

• Lifting a piano from the street to the fourth floor of a building
• Separating a mixture of coins into pennies, nickels, dimes, and quarters
• Removing the metal objects from trash at a recycling center
• Removing the glass objects from trash at a recycling center

What makes a material a good conductor?

• A conductor makes it difficult for electricity to flow through it.
• A conductor allows electricity to flow through it.
• A conductor transforms electrical energy into other forms of energy.
• None of the other answer choices

How do electric charges flow in a circuit?

• From one end of the circuit to the other end
• From a point in the middle of the circuit to two ends
• In a loop around the circuit
• All of the other answer choices

Electrons are flowing through the wires of a circuit. Which of these actions will stop the electrons from flowing?

• Bend one of the wires without breaking it.
• Coat the wires with thick plastic.
• Replace the wires in the circuit with thicker wires.
• Remove the battery or other power source from the circuit.

In order for electricity to flow, it must follow a(n)

• network of wires called a grid. 
• complete path called an open circuit.
• complete path called a closed circuit.
• None of the other answer choices

Jane sees a battery on one table and a light bulb on another table. She may not move either the battery or the light bulb. What does she need to complete a circuit and light the light bulb?

• One wire that is twice the distance between the battery and the light bulb
• Two wires, each long enough to connect the battery and the light bulb
• Another battery that she can place next to the light bulb
• Another light bulb that she can place next to the battery