Resistance and Electric Current

These flashcards cover key concepts related to resistance and electric current, including definitions, units of measurement, relationships, and effects in circuits.

What is electric current?

The flow of electric charge.

What is the unit for electric current?

Amperes (A).

What do you measure current with? Where is it placed in the circuit?

Ammeter; placed in series.

What is potential difference?

The difference in electric potential energy per unit charge.

What is the unit for potential difference?

Volts (V).

What do you measure potential difference with? Where is it placed in the circuit?

Voltmeter; placed in parallel.

What is the difference between a series and a parallel circuit?

Series has one pathway, while parallel has multiple pathways.

How does current behave in a series circuit?

Current remains the same throughout the circuit.

How does current behave in a parallel circuit?

Current divides among the pathways.

What happens to the potential difference as resistance increases?

Potential difference increases.

What does the equation V = I × R represent?

The relationship between voltage (V), current (I), and resistance (R).

What factor increases the resistance in a wire?

Length of the wire.

What is the effect of a longer wire on current?

The current decreases.

Why does a wire heat up when made longer?

Increased collisions with metal ions result in heat.

How does higher resistance affect components in a circuit?

It limits the electricity each component receives.

Why might a high resistance be useful in a circuit?

It prevents overheating and allows control over current flow.