All Flashcards
Compare and contrast electric potential and electric potential energy.
Electric Potential: Potential energy per unit charge (V = U/q). Scalar quantity. | Electric Potential Energy: Energy a charge possesses due to its position in an electric field (U = qV). Scalar quantity.
What are the key differences between series and parallel circuits?
Series: Components connected end-to-end; same current through each; total resistance is the sum of individual resistances. | Parallel: Components connected side-by-side; same voltage across each; reciprocal of total resistance is the sum of reciprocals of individual resistances.
Compare and contrast step-up and step-down transformers.
Step-Up Transformer: Increases voltage; N_s > N_p. | Step-Down Transformer: Decreases voltage; N_s < N_p.
Differentiate between electric force and electric field.
Electric Force: The force exerted on a charge due to an electric field (F = qE). Vector quantity. | Electric Field: The force per unit charge at a point in space (E = F/q). Vector quantity.
Compare and contrast conventional current and electron flow.
Conventional Current: Defined as the direction positive charges would flow. | Electron Flow: The actual movement of electrons, which is opposite to the direction of conventional current.
Describe the process of charging a capacitor in an RC circuit.
- Voltage source applies potential difference. 2. Current flows, accumulating charge on capacitor plates. 3. Voltage across capacitor increases exponentially. 4. Current decreases exponentially as capacitor charges. 5. Capacitor is fully charged when voltage equals source voltage.
Outline the steps to analyze a complex circuit using Kirchhoff's rules.
- Identify junctions and loops. 2. Apply junction rule: ΣI_in = ΣI_out at each junction. 3. Apply loop rule: ΣV = 0 around each closed loop. 4. Solve the system of equations for unknown currents and voltages.
Explain how a transformer changes voltage.
- Alternating current flows through the primary coil. 2. This creates a changing magnetic field. 3. The changing magnetic field induces a voltage in the secondary coil. 4. The voltage ratio is determined by the turns ratio:
Describe the process of electric current flowing through a wire.
- A potential difference (voltage) is applied across the wire. 2. Free electrons in the wire experience an electric force. 3. These electrons drift in a specific direction, creating a net flow of charge. 4. The rate of this flow is the electric current, measured in Amperes.
What are the steps to determine the equivalent resistance of resistors in parallel?
- Identify all resistors connected in parallel. 2. Take the reciprocal of each individual resistance. 3. Sum all of the reciprocals. 4. Take the reciprocal of the sum to find the total equivalent resistance:
What is the effect of increasing the distance between two charges on the electric force between them?
The electric force decreases according to Coulomb's Law (inverse square relationship).
What happens when a dielectric material is inserted between the plates of a capacitor?
The capacitance increases.
What is the effect of increasing the area of the plates of a parallel plate capacitor?
The capacitance increases.
What happens when a changing magnetic field passes through a loop of wire?
An electromotive force (EMF) is induced in the loop, according to Faraday's Law.
What is the effect of increasing the number of turns in the secondary coil of a transformer?
The voltage in the secondary coil increases (if it's a step-up transformer) or decreases (if it's a step-down transformer), according to the turns ratio.
What happens when current flows through a wire?
A magnetic field is created around the wire.