Electric Current and Circuits

These flashcards focus on key concepts related to electric current, Ohm's law, resistors, and electrical power, providing essential definitions and calculations.

What is Ohm's law?

The current in a wire is proportional to the potential difference between its ends.

What formula represents Ohm's law?

V = IR, where V is voltage, I is current, and R is resistance.

How do you calculate current, I?

Current I = Q/t, where Q is charge and t is time.

What is the unit for electric current?

The unit for electric current is the Ampere (A).

What is resistance?

Resistance is the opposition to the flow of electric current.

What is the formula for calculating total resistance in a series circuit?

Req = R1 + R2 + R3.

What is the formula for calculating total resistance in a parallel circuit?

1/Req = 1/R1 + 1/R2 + 1/R3.

What is resistivity?

Resistivity is a material property that quantifies how strongly a given material opposes the flow of electric current.

What is the formula for resistivity?

R = ρ(l/A), where R is resistance, ρ is resistivity, l is length, and A is the cross-sectional area.

What is electric power, P?

Power is the rate at which electrical energy is converted to another form of energy, measured in Watts.

How is electric power calculated?

P = IV, where P is power, I is current, and V is voltage.

What is an ammeter used for?

An ammeter measures the current flowing through a circuit.

What is a voltmeter used for?

A voltmeter measures the potential difference (voltage) across two points in a circuit.

What does a multimeter measure?

A multimeter measures voltage, current, and resistance.

In a circuit, what does a resistor do?

A resistor restricts the flow of current.

If a battery's voltage drops, what happens to the current assuming constant resistance?

The current will decrease.