- To understand the measurement of two basic physical quantities that describes the operation of electric circuits: current and voltage using current and voltage sensor (ammeter and voltmeter, eventually);
- To understand that current is the same at all points in simple circuits;
- To understand how voltage is distributed across different parts of a simple electric circuit.
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- Battery (e.g.zinc-carbon or fresh alkaline, 4,5V), two bulbs (e.g. 4,5V/0,3A), leads, computer, interface and software (e.g. COACH 6), current sensor, voltage sensor (ammeter and voltmeter eventually)
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| Divide the class into small groups of 2-3 and hand out Classroom Material: Measuring current and voltage. This is a simple activity aimed at developing basic skills concerning measurement of current and voltage in a simple electric circuit with the help of sensors and understanding about current and voltage in the simple circuit. That’s why it is very important to work in small groups so each student has a chance to manipulate with the circuit components. Students learn that to measure the voltage across an element in a circuit the voltage sensor has to be connected in parallel and to measure the current flowing through it the current sensor has to be connected In series with it. They learn that the current is the same at different points of a simple electric circuit and that it is not used up by the circuit element. They learn how the voltage is distributed across different parts of the electric circuits. Students working in groups of 2-3 are engaged in a guided inquiry answering the questions and predicting the behaviour of the circuit following gradually the instructions in the worksheet. In case the sensors are not available, the activity can be carried out with the help of ammeter and voltmeter. Industrial content can be emphasized mentioning that the sensors aimed at measuring not only current and voltage are widely used nowadays. |
- Is the current the same at different points of a simple electric circuit? Explain.
- Is the voltage the same across the battery and the bulb in a simple electric circuit? Explain.
- Is there a circuit element with zero voltage across it?
- What is the voltage expected to be at the two ends of the same wire?
- How is the voltage across a battery influenced by the number of bulbs connected in series?
- How is the current through a circuit influenced by the number of bulbs connected in series?
- Is the battery a source of a constant current or a constant voltage?
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