Understanding Current Electricity

Which of the following is a representation of Ohm's law?

• V = I * R.

• 
• I = V + R

• R = V - I

• 

Kirchhoff’s junction rule is a reflection of

• conservation of current density vector.

• conservation of charge.

• the fact that the momentum with which a charged particle approaches a junction is unchanged (as a vector) as the charged particle leaves the junction.

• the fact that there is no accumulation of charges at a junction.

How do you calculate electrical power in a circuit?

• P = V + I

• P = V × I

• P = V / I

• P = I² × R

What is the difference between series and parallel circuits?

• Series circuits have multiple paths for current, while parallel circuits have a single path.

• In series circuits, the voltage is divided, while in parallel circuits, the current is divided.

• Series circuits can operate without a power source, while parallel circuits require one.

• Series circuits have a single path for current, while parallel circuits have multiple paths.

Define capacitance and explain its significance in circuits.

• Capacitance is the resistance to electrical flow, measured in ohms (Ω).

• Capacitance is the ability of a component to store electrical charge, measured in farads (F).

• Capacitance is the speed at which a circuit operates, measured in hertz (Hz).

• Capacitance is the power consumption of a component, measured in watts (W).

What is the formula for calculating the capacitance of a parallel plate capacitor?

• C = (ε₀ * d) / A

• C = ε₀ * (A + d)

• C = (ε₀ * A) / d

• C = (A * d) / ε₀

Explain the concept of resistivity and its relation to conductivity.

• Resistivity is only relevant in superconductors, while conductivity applies to all materials.

• Resistivity measures the speed of current flow, while conductivity measures resistance.

• Resistivity and conductivity are the same concept, just different terms for the same property.

• Resistivity is the opposition to current flow in a material, while conductivity is its ability to conduct current; they are inversely related.

How does temperature affect the resistivity of a conductor?

• Temperature increases the resistivity of a conductor.

• Higher temperature decreases the resistivity of a conductor.

• Resistivity is only affected by the material type, not temperature.

• Temperature has no effect on resistivity.

What is the total resistance in a series circuit with three resistors?

• R_total = R1 * R2 * R3

• R_total = R1 - R2 - R3

• R_total = R1 / R2 / R3

• R_total = R1 + R2 + R3

How do you find the equivalent resistance in a parallel circuit?

• R_eq = R1 + R2 + ... + Rn

• R_eq = 1 / (1/R1 + 1/R2 + ... + 1/Rn)

• R_eq = R1 * R2 / (R1 + R2)

• R_eq = R1 - R2