Physics Unit 8 - Electricity (Practice Test)

Front

What happens to the electric force between two point charges when the distance between them is tripled?

Back

The electric force decreases by a factor of 1/9, according to Coulomb's law, which states that force is inversely proportional to the square of the distance between charges.

Front

Define electric field intensity.

Back

Electric field intensity (E) is the force (F) experienced by a unit positive charge (q) placed in the field, expressed as E = F/q. It is measured in Newtons per Coulomb (N/C).

Front

What is the formula to calculate power in an electrical circuit?

Back

Power (P) is calculated using the formula P = V^2/R, where V is the voltage and R is the resistance.

Front

What is the equivalent resistance of resistors in series?

Back

The equivalent resistance (R_eq) of resistors in series is the sum of their resistances: R_eq = R1 + R2 + R3 + ...

Front

State Coulomb's law.

Back

Coulomb's law states that the electric force (F) between two point charges is directly proportional to the product of the magnitudes of the charges (q1 and q2) and inversely proportional to the square of the distance (r) between them: F = k * (q1 * q2) / r^2.

Front

What is the unit of electric charge?

Back

The unit of electric charge is the Coulomb (C).

Front

How does the electric field intensity change with distance from a point charge?

Back

The electric field intensity decreases with the square of the distance from the charge, following the formula E = k * q / r^2.

Front

What is the relationship between current (I), voltage (V), and resistance (R) in a circuit?

Back

Ohm's Law states that I = V/R, meaning current is directly proportional to voltage and inversely proportional to resistance.

Front

What is the significance of a lightbulb having equal current in a circuit?

Back

If all lightbulbs in a circuit have equal current, it indicates that they are connected in parallel, where the voltage across each bulb is the same.

Front

Calculate the power dissipated in a resistor with a voltage of 5.0 V and resistance of 10.0 Ω.

Back

Using the formula P = V^2/R, P = (5.0^2)/10.0 = 2.5 W.