Complete and Incomplete Circuits

Which material could fill in the question mark for circuit B to create a complete circuit?

• copper wire

• plastic spoon

• wool

• construction paper

Which of the following could make the bulb in circuit A brighter? 

• adding another light bulb
• putting in a switch 
• adding another battery
• reversing the direction of the battery 

If an object is NOT added to circuit B, and the wires are not attached, which of the following would describe the circuit?

• complete circuit

• closed circuit

• incomplete circuit

• series circuit

What other objects could take the place of the light bulb to create a complete circuit? 

• buzzer 
• motor 
• both buzzer and motor 
• neither buzzer nor motor 

An object is added to the spot of circuit B. Why might the light bulb still not light? 

• the object added was an insulator 
• the object added was a conductor 
• the object was made of metal 
• the object created a closed circuit

What is the purpose of the rubber coating on wires? 

• serves as a conductor for the circuit
• prevents the light bulb from using up too much energy 
• serves as an insulator for protection 
• closes the circuit 

Which is NOT a required part of a complete circuit designed to light a light bulb? 

• battery
• switch 
• wire
• light bulb 

A circuit is considered open when...

• the switch completes the circuit

• the light bulb is lit

• the circuit is incomplete

• a buzzer is used instead of a light bulb

What is the source of energy in the circuits above? 

• light bulb
• battery
• wire 
• conductive object 

What will happen if there is a break where the X is located?

• The first light bulb will not be lit.

• The second light bulb will not be lit.

• All light bulbs will be lit.

• No light bulbs will be lit.