16. An open circuit is a broken circuit. 17. A switch controls the circuit by opening and closing it. 18. In a circuit with unjointed wires, the motor will not work. 19.When the switch is off, the circuit is open. Therefore, the circuit won't work. 20. If the switch is off, the circuit is closed. Therefore, the circuit will work. 21. Each turn of the wire adds more force to the electromagnet. 22. An electromagnet can be made stronger by using more coil of wire. 23. The number of turns of wire on the core can affect the strength of electromagnets. 24. The lesser the size of the iron core, the stronger magnetism on electromagnet has.
