Electricity and Circuits — Answer Key
Part A: Fix the Sentence
Each sentence has an error. Rewrite it correctly on the line.
1. Fix the sentence:
A closed circuit has a gap so electricity cannot flow through the wires.
Corrected: A closed circuit has no gap, so electricity can flow in a complete loop through the wires.
The corrected sentence is: "A closed circuit has no gap, so electricity can flow in a complete loop through the wires.". The original sentence "A closed circuit has a gap so electricity cannot flow through the wires." contained an error that needed to be fixed.
2. Fix the sentence:
Rubber is a good conductor of electricity, which is why wires are coated in rubber.
Corrected: Rubber is a good insulator that blocks electricity, which is why wires are coated in rubber for safety.
The corrected sentence is: "Rubber is a good insulator that blocks electricity, which is why wires are coated in rubber for safety.". The original sentence "Rubber is a good conductor of electricity, which is why wires are coated in rubber." contained an error that needed to be fixed.
3. Fix the sentence:
A battery pushes electricity through a circuit using magnetism.
Corrected: A battery pushes electricity through a circuit using chemical energy that is converted into electrical energy.
The corrected sentence is: "A battery pushes electricity through a circuit using chemical energy that is converted into electrical energy.". The original sentence "A battery pushes electricity through a circuit using magnetism." contained an error that needed to be fixed.
Part B: Fill in the Blank
Write the missing word or number on each line.
1. A material that allows electricity to flow through it is called a conductor.
Conductors (like copper and aluminum) allow electrons to move freely, letting electricity flow through them.
2. A material that blocks the flow of electricity is called an insulator.
Insulators (like rubber and plastic) hold their electrons tightly, preventing electric current from passing through.
3. A complete path that electricity follows is called a circuit.
An electric circuit is a closed loop through which electric current can flow continuously.
4. A battery provides the energy that pushes electricity through a circuit.
A battery converts chemical energy into electrical energy, creating the voltage that drives current through a circuit.
Part C: Short Answer
Answer each question in one or two complete sentences.
1. What is the difference between an open circuit and a closed circuit?
Sample answer: A closed circuit is a complete loop with no gaps, so electricity can flow. An open circuit has a break or gap, so electricity cannot flow and the device will not work.
Circuit completeness is key: closed circuits allow current; open circuits stop it. A switch opens and closes a circuit.
2. Why should you never touch electrical outlets or frayed wires with wet hands?
Sample answer: Water is a conductor of electricity. Touching outlets or damaged wires with wet hands lets electricity flow through the water into your body, which can cause a dangerous shock.
Water's dissolved minerals make it conductive. Wet skin significantly lowers the body's resistance, making electric shock more dangerous.