Total Charge with Variable Density Total Charge on Sphere (Variable Density) Given Radius R = 30 cm = 0.3 m Charge density: ρ(r) = 200 (r / R) pC/m³ Step 1: Convert to SI Units ρ(r) = 200 × 10 -12 × (r / R) Step 2: Use Charge Formula Q = ∫₀ᴿ ρ(r) · 4πr² dr Step 3: Substitute Q = ∫₀ᴿ (200 × 10 -12 × r/R) · 4πr² dr Step 4: Simplify Q = (200 × 10 -12 × 4π / R) ∫₀ᴿ r³ dr Step 5: Integrate ∫ r³ dr = r⁴ / 4 Q = (200 × 10 -12 × 4π / R) × (R⁴ / 4) Step 6: Simplify Q = 200π × 10 -12 × R³ Step 7: Substitute R = 0.3 R³ = (0.3)³ = 0.027 Q = 200π × 10 -12 × 0.027 Q = 5.4π × 10 -12 Final Answer: Q ≈ 1.7 × 10 -11 C Or, 17 pC Option A

  Z-Parameters of Lattice Network Z-Parameters of a Lattice Network Lattice Network Setup A lattice network typically has two diagonal impedances: Za (one diagonal) Zb (the other diagonal) The Easy Trick z11 = z22 = (Za + Zb) / 2 z12 = z21 = (Zb - Za) / 2 How to Remember It Sum → diagonal terms → divide by 2 Difference → off-diagonal terms → divide by 2 Add → self impedance (z11, z22) Subtract → mutual impedance (z12, z21) z = (1/2) × [ (Za + Zb) (Zb - Za) (Zb - Za) (Za + Zb) ] Symmetry shows: z11 = z22 z12 = z21 When This Works Standard symmetric lattice network ...

  Minimum Slew Rate of Op-Amp Minimum Slew Rate of Op-Amp What is Slew Rate? Slew rate is the maximum rate of change of output voltage of an op-amp. SR = dV / dt (V/μs) Minimum Slew Rate Formula To avoid distortion: SR min = 2π f V peak f = frequency of signal V peak = peak output voltage Why This Matters If slew rate is too low, output cannot follow input Signal becomes distorted (triangular instead of sine) Example Given: f = 20 kHz V peak = 10 V SR min = 2π × 20000 × 10 ≈ 1.26 V/μs Required slew rate ≥ 1.26 V/μs Typical Values General-purpose op-amp (LM741): ~0.5 V/μs Audio op-amps: 5–20 V/μs High-speed op-amps: 100+ V/μs Summary The minimum slew rate depends on signal freq...

  Choke Input Filter Choke Input Filter A well-designed choke input filter is a type of power supply filter used to smooth the output of a rectifier (like in DC power supplies). It uses an inductor (choke) as the first component right after the rectifier, followed by a capacitor. Basic Structure Rectifier → Choke (L) → Capacitor (C) → Load What Makes It Well-Designed? Critical Inductance is satisfied: The choke must have enough inductance to keep current flowing continuously. This minimum value is called critical inductance. Low ripple output: A good design significantly reduces AC ripple in the DC output. The choke resists sudden changes in current. Proper load current: Works best when the load current is above a certain minimum level. Too light a load results in poor filter...

    UGC-NET Electronic Science Question Paper With Answer Key and Full Explanation [Dec 2024] UGC-NET Electronic Science Question Paper With Answer Key Download Pdf [Dec 2024 / Jan 2025] (Exam held 27-01-2025) Download Question Paper                  2025 | 2024 | 2023 | 2022 | 2021 | 2020 UGC-NET Electronic Science  Jan 2025 Answers with Explanations Q.1 Answer. Option (3) Q.2 Answer. Option (3) Q.3 Answer. Option (3) Q.4 Answer. Option (4) Q.5 Answer. Option (3) Q.6 Answer. Option (3) Q.7 Answer. Option (4) Q.8 Answer. Option (3) Q.9 Answer. Option (3) Q.10 Answer. Option (4) Q.11 Answer. Option (3) solution hint: 20*0.8 = 16KW ; 16/0.85 = 18.82 Q.12 Answer. Option (2) solution hint: E = V/d; j=epsilon*dE/dt Q.13 Answer. Option (3) Q.14 Answer. Option (3) Q.15 Answer. Option (2) solution hint: 1/2*pi*r Q.16 Answer. Option (3) solution hint: 1/RC Q.17 Answer. Option (3) Q.18 Answer. Option (2) solution hint: Fto...

  Q Factor - Bandpass Filter Q Factor in Band-Pass Filter Definition The Q factor (Quality Factor) defines how selective a band-pass filter is. It determines how narrow or wide the frequency response is around the center frequency. Formula Q = f₀ / BW Where: f₀ = center frequency BW = bandwidth = (fH - fL) Circuit Form (RLC Bandpass) Q = (1/R) √(L/C) or Q = ω₀L / R Effect of Q Factor Q Value Behavior Low Q (< 1) Wide bandwidth, less selective Medium Q (5–10) Balanced selectivity High Q (> 20) Narrow bandwidth, highly selective Summary The Q factor controls the sharpness of the band-pass filter response. Higher Q means sha...

  Neuromorphic Computing Neuromorphic Computing Introduction Neuromorphic computing is a computing paradigm inspired by the human brain, where memory and processing are integrated to achieve efficient and parallel computation. Key Concept Unlike traditional von Neumann architecture, neuromorphic systems mimic neurons and synapses, enabling simultaneous computation and data storage. Neurons act as processing units Synapses act as memory elements Core Components Artificial Neurons: Perform computation Synapses (RRAM devices): Store weights Spiking Neural Networks: Event-driven processing Advantages Low power consumption Massive parallelism Real-t...

Hybrid CNN + Radiomics for PET DICOM Classification An advanced deep learning approach combining spatial feature extraction with quantitative medical imaging features. ⚙️ Setup 📊 Dataset 🧠 Hybrid Model 📈 Evaluation Imports Data Prep Architecture Training ROC-AUC 📂 Project Contents & Features ▼ ✅ Loads PET DICOM images ✅ Extracts simple radiomics features ✅ Combines CNN + radiomics (hybrid model) ✅ Trains and evaluates using ROC-AUC 1. Environment Setup & Imports We initialize the environment using PyTorch and necessary medical imaging libraries like Pydicom and SimpleITK....