Electricity Investigation 2 Review

Circuits A circuit is a pathway through which electric current flows. A circuit must be complete to work properly.

A circuit must be complete in order to work. Can you tell what is wrong with each of these circuits? This circuit needs a wire from the bulb to the negative side of the battery. This wire from the negative end should connect to the other end of the bulb. This circuit needs one wire from the bulb to go to the positive side of the battery. Energy only flows from the positive and negative ends of the battery, not from the side.

Electricity Receivers A light bulb is a receiver that produces light. A motor is a receiver that produces motion.

Components A D-cell is one component (part) of a circuit. It is the SOURCE of the electricity.

Switches A switch is used to open and close a circuit.

Insulators An insulator is a material that prevents electricity from flowing through the circuit. Some examples of insulators are: plastic, cardboard, magnetite, and wood.

Conductors A conductor is a material that allows electricity to flow through the circuit. (It drives the electricity through the circuit, just like a conductor drives a train!) All metals, including aluminum foil, pennies, and nails, are conductors.

Schematic drawings Schematic drawings are used to represent circuits on a piece of paper.

Time for a Quiz! Which of these items are conductors? Penny Paper clip Aluminum foil All of the above None of the above

D All items made of any type of metal are conductors, including foil, pennies, paper clips, and nails. Items that are not made of metal are insulators!

A switch is used to…. A. Open a circuit B. Close a circuit C. Neither A nor B D. Both A and B

D Switches are used to open and close circuits. When you turn on a light switch in your house, it closes the circuit so that electricity can be received by the light bulb. When you turn off the switch, the circuit opens and the electricity does not flow to the receiver.

Will this bulb light?

NO One wire needs to touch the SIDE of the bulb to complete the circuit. (Remember, there is a little wire inside the bulb that connects the metal on the side to the bottom, so you need one wire at each point.)

Will this bulb light?

NO One wire needs to touch the BOTTOM of the bulb to complete the circuit.

Will this bulb light?

YES There is a complete circuit in this drawing! Even though there is only one wire, the energy from the D-cell goes through the side of the bulb where it is touching to connect the circuit.

Will this bulb light?

YES There is a complete circuit in this drawing, too!

Which component provides the electric power in a circuit? D-cell Bulb Motor Wires All of the above

A The D-cell is the source of power in a circuit.

Science is electrifying!