# Electricity - resistance

1

 V=  V          I=  A

Start. An unknown resistor is connected to a variable voltage source as shown above. You can vary the voltage by using the slider. To read ammeter and voltmeter values put the mouse-cursor onto each of them. Plot the measurements into the (V,I)-graph.

What is the resistance of the unknown resistor?   (Answer).

2

 V=  V          I=  mA

Start. An unknown resistor is connected to a variable voltage source as shown above. You can vary the voltage by using the slider. To read ammeter and voltmeter values put the mouse-cursor onto each of them. Plot the measurements into the (V,I)-graph.

What is the resistance of the unknown resistor?    (Answer).

3

 V=  V          I=  mA

Start. An unknown part is connected to a variable voltage source as shown above. You can vary the voltage by using the slider. To read ammeter and voltmeter values put the mouse-cursor onto each of them. Plot the measurements into the (V,I)-graph.

Is the unknown part a resistor?    (Answer).

Determine the resistance of the part when a current of 40 mA is sent through it?   (Answer).

4

 Part 1        Part 2        Part 3

Put each of the three parts into the circuit above. Use the slider to vary the voltage. The voltage is in volt and the current in milliamps.

Which part obeys Ohms law?    (Answer).

Move on to Electricity - power

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