
WAECAFRICA.COM BEST SCHOOL GUIDE
February 14, 2025 at 09:42 AM
*Energy:*
1. *Electric Potential Energy (EPE)*: The energy stored in a charged object or a system of charged objects.
- Formula: EPE = k * q1 * q2 / r
- where: k = Coulomb's constant, q1 and q2 = charges, r = distance between charges
2. *Electric Potential (V)*: The potential difference between two points in an electric field.
- Formula: V = EPE / q
- where: EPE = electric potential energy, q = charge
3. *Energy Stored in a Capacitor (E)*: The energy stored in a capacitor.
- Formula: E = (1/2) * C * V^2
- where: C = capacitance, V = voltage
4. Electric energy = power × time ( using any of the below formula for power that is P = IV or p = V²/R or P = I²R)
*Power:*
1. *Electric Power (P)*: The rate at which energy is transferred or converted in an electric circuit.
- Formula: P = V * I
- where: V = voltage, I = current
2. *Power Dissipated in a Resistor (P)*: The power dissipated in a resistor due to Joule heating.
- Formula: P = I^2 * R
- where: I = current, R = resistance
3. *Power Stored in an Inductor (P)*: The power stored in an inductor due to the magnetic field.
- Formula: P = (1/2) * L * I^2
- where: L = inductance, I = current
*Other Formulas:*
1. *Ohm's Law*: The relationship between voltage, current, and resistance in an electric circuit.
- Formula: V = I * R
- where: V = voltage, I = current, R = resistance
2. *Capacitor Charging and Discharging*: The equations that describe the charging and discharging of a capacitor.
- Formula: Q = C * V (charging),
- where: Q = charge, C = capacitance, V = voltage,