Science 7 · Unit 9: Electricity · Cambridge Lower Secondary Science Stage 7

Questions

1. 1. What happens to the electrons in a wire when a current flows?

   • They flow around the circuit.
   • They move randomly in the circuit.
   • They do not move in the circuit.
   • They vibrate more slowly.
   Check

2. 2. What is an electric current?

   • electrons stuck in one place
   • a type of wire
   • a store of electrons in a cell
   • a flow of electrons around a circuit
   Check

3. 3. In a metal that is not in a circuit, how do the free electrons move?

   • all in the same direction
   • randomly
   • not at all
   • only towards the positive end
   Check

4. 4. True or false: Electrons in metal wires are free to move.

   • True
   • False
   Check

5. 5. True or false: Electrons have a positive charge.

   • True
   • False
   Check

6. 6. What charge does an electron have?

   • negative
   • positive
   • neutral
   • no charge at all
   Check

7. 7. Which charges attract each other?

   • positive and negative
   • positive and positive
   • negative and negative
   • neutral and neutral
   Check

8. 8. A cell has two terminals. What are they?

   • neutral and positive
   • two positive terminals
   • neutral and negative
   • positive and negative
   Check

9. 9. What does a cell store that can be changed to electrical energy in a circuit?

   • sound energy
   • light energy
   • chemical energy
   • thermal energy
   Check

10. 10. What is a battery?

    • a type of lamp
    • two or more cells joined together
    • a single cell
    • a wire with no switch
    Check

11. 11. In a circuit, which way do electrons flow?

    • away from the negative terminal, towards the positive terminal
    • away from the positive terminal, towards the negative terminal
    • in both directions at once
    • only inside the cell
    Check

12. 12. Why are electrons attracted towards the positive terminal of a cell?

    • Electrons have a negative charge, and opposite charges attract.
    • Electrons have a positive charge, and like charges attract.
    • Electrons have no charge.
    • The positive terminal is closer.
    Check

13. 13. The arrows on a circuit show electrons flowing out of the left end of the cell. Which end of the cell is negative?

    • the left end
    • the right end
    Check

14. 14. Are the electrons used up in a lamp?

    • No, they flow through the lamp and back to the cell.
    • Yes, the lamp uses up the electrons to make light.
    Check

15. 15. What happens to the electrons if there is a break in the circuit?

    • They flow faster.
    • They all stop flowing.
    • Only half of them stop.
    • They flow backwards.
    Check