Understanding V=IR and Electrical Graphs

What does the equation V=IR represent in an electrical circuit?

• Resistance equals voltage divided by current

• Current equals voltage times resistance

• Voltage equals resistance divided by current

• Voltage equals current times resistance

If a circuit has a constant resistance, what happens to the current when the voltage is increased?

• The current remains the same

• The current decreases

• The current increases proportionally

• The current becomes zero

How does the graph of current versus potential difference look for a circuit with only wires or resistors?

• A curved line

• A straight line

• A circular line

• A zigzag line

What happens to the resistance of a filament lamp as the current increases?

• The resistance becomes zero

• The resistance decreases

• The resistance increases

• The resistance remains constant

Why do diodes only allow current to flow in one direction?

• They have a high resistance in the forward direction

• They have a low resistance in both directions

• They have no resistance at all

• They have a high resistance in the reverse direction