Top Repeat Calc Apply Mesh Analysis to find current/power in a specific resistor. [See Diagram in PDF]
Pg 16
Dec 24, Apr 25, July 25, July 24, Feb 24, June 23, Aug 23
Method:
1. Identify loops (meshes). Assign currents I1, I2, I3.
2. Apply KVL to each loop: Σ(Voltage Rises) = Σ(Voltage Drops).
3. Solve simultaneous equations for I values.
4. Branch current = (I1 - I2) or similar depending on direction.
Top Repeat Calc Apply Nodal Analysis to find Node Voltages (V1, V2). [See Diagram in PDF]
Pg 19
Dec 24, Apr 25, July 25, July 24, Feb 24, May 24, Aug 23
Method:
1. Identify Nodes. Select one Reference Node (0V).
2. Apply KCL at each non-reference node: Σ(Currents leaving) = 0.
3. Express currents as (V_node - V_neighbour)/R.
4. Solve for V1, V2.
High Yield Star-Delta Transformation. Find Equivalent Resistance. [See Diagram in PDF]
Pg 22
Feb 25, Apr 25, Dec 23, July 24, Mar 24
Delta to Star:
Ra = (R1*R2) / (R1+R2+R3)
Star to Delta:
R12 = Ra + Rb + (Ra*Rb)/Rc
High Yield Superposition Theorem. Find current in a resistor.
Pg 30
Apr 25, July 25, Dec 23, Aug 23, May 24
Statement: In a linear bilateral network containing more than one source, the response is the algebraic sum of responses caused by each source acting alone.
Step: Turn off other sources (Short voltage sources, Open current sources).
Calc Thevenin's / Norton's Theorem. Find Load Current.
Pg 23
July 24, Feb 24, June 23
I_load = Vth / (Rth + RL) [Thevenin]
I_load = (I_N * Rn) / (Rn + RL) [Norton]
Must Do RC Series Transient (Charging/Discharging). Derive V/I equations. Calc Time Constant.
Pg 30
Feb 25, Dec 24, Apr 25, July 24, Feb 24, June 23
Charging Voltage: v(t) = V(1 - e^(-t/RC))
Charging Current: i(t) = (V/R) * e^(-t/RC)
Time Constant (τ): R * C
Calc RLC Series Circuit. Find Resonance Freq, Q-Factor, Voltages.
Pg 2
Apr 25, Mar 24, May 24
Resonance Freq (fr) = 1 / (2π√(LC))
Quality Factor (Q) = (1/R) * √(L/C)
At Resonance: Z = R, I = V/R.
Graph Waveform Analysis. Find RMS, Average, Form Factor.
Pg 28
Dec 24, July 24, June 23, Aug 23
RMS: Root of the Mean of the Squares.
Average: Mean over half cycle (for symmetric).
Form Factor: RMS Value / Average Value.
Theory Magnetic Circuit Concepts. MMF, Reluctance, Flux, Fringing, Leakage. Analogy with Electric.
Pg 18
Feb 25, July 24, Mar 24, June 23, Aug 23
- MMF (Amp-Turns): Analogous to EMF. Force driving flux.
- Reluctance (S): Analogous to Resistance. Opposition to flux. S = l / (μA).
- Fringing: Spreading of flux lines at air gaps.
Top Repeat Star/Delta Relations. Derive Line vs Phase V/I. Numericals on Load Power.
Pg 21
Feb 25, Dec 23, Aug 23, July 24, June 23
Star: IL = Iph, VL = √3 * Vph
Delta: VL = Vph, IL = √3 * Iph
Power: P = √3 * VL * IL * cos(Φ)
Calc 2-Wattmeter Method. Find Power & PF.
Pg 21
Dec 24, July 24, Aug 23, May 24
Total Power = W1 + W2
PF Angle Φ = tan⁻¹ [ √3 * (W1 - W2) / (W1 + W2) ]
High Yield Rectifiers (Half, Full, Bridge). Efficiency & Ripple Factor.
Pg 21
Dec 23, Aug 23, July 24, June 23, May 24
Efficiency (max): HWR = 40.6%, FWR = 81.2%.
Ripple Factor: HWR = 1.21, FWR = 0.48.
Diagram BJT Transistor. Construction, Amplifier/Switch modes.
Pg 12
Dec 24, July 24, Dec 23, Aug 23, May 24
Active Mode: E-B fwd bias, C-B rev bias -> Acts as Amplifier.
Saturation Mode: Both fwd bias -> Acts as Closed Switch (ON).
Cutoff Mode: Both rev bias -> Acts as Open Switch (OFF).
Rare Special Diodes (Zener, LED, Photo).
Pg 12
Dec 23, Aug 23, July 24
Zener: Voltage Regulator (Rev Bias).
LED: Light Emitter (Fwd Bias).
Photodiode: Light Detector (Rev Bias).
Must Do Logic Circuit Analysis. Write Output Expression & Truth Table. [See Diagram in PDF]
Pg 21
Dec 23, Aug 23, June 23, May 24, Dec 24
Math Number Conversion. (Hex/Octal/Binary/Decimal).
Pg 3
All Years
Tip: Use binary as a bridge. (e.g., Hex -> Binary -> Octal).
Hex to Bin: 1 hex digit = 4 bits.
Octal to Bin: 1 octal digit = 3 bits.
Design Full Adder using Half Adders / XOR using NAND.
Pg 6
Aug 23, Dec 23, July 24