Define electric charge.
A fundamental property of matter that causes it to experience a force when placed in an electromagnetic field.
What is electric potential (V)?
The potential energy per unit charge at a point in an electric field, measured in volts (V). \(V = \frac{U}{q}\)
Define capacitance (C).
The ability of a capacitor to store charge, measured in farads (F). \(C = \frac{Q}{V}\)
What is electric current (I)?
The rate of flow of electric charge, measured in amperes (A). \(I = \frac{\Delta Q}{\Delta t}\)
Define resistance (R).
The opposition to the flow of electric current, measured in ohms (ฮฉ). \(R = \frac{V}{I}\)
What is a magnetic field (B)?
A region of space where a magnetic force can be detected, measured in teslas (T).
Define magnetic flux (ฮฆ).
A measure of the total magnetic field passing through a given area. \(\Phi = BA\cos(\theta)\)
Describe the process of charging a capacitor in an RC circuit.
1. 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.
1. Identify junctions and loops. 2. Apply junction rule: ฮฃI_in = ฮฃI_out at each junction. 3. Apply loop rule: ฮฃV = 0 around each closed loop. 4. Solve the system of equations for unknown currents and voltages.
Explain how a transformer changes voltage.
1. 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: \(\frac{V_p}{V_s} = \frac{N_p}{N_s}\)
Describe the process of electric current flowing through a wire.
1. 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?
1. 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: \(\frac{1}{R_{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \frac{1}{R_3} + ...\)
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.
