⚡ Average EMF Induced in a Rectangular Coil
📘 Question:
A rectangular loop of wire with dimensions 0.30 m × 0.20 m and 60 turns is placed in a magnetic field. The field is perpendicular to the loop and drops from 1.2 T to 0.0 T in 0.150 seconds. What is the average induced emf?
✅ Step-by-Step Explanation:
🔹 Step 1: Given Data
- Length = 0.30 m
- Width = 0.20 m
- Turns = 60
- Initial Magnetic Field = 1.2 T
- Final Magnetic Field = 0 T
- Time Interval = 0.150 s
🔹 Step 2: Area of Loop
A = 0.30 × 0.20 = 0.06 m²
🔹 Step 3: Magnetic Flux Change
Φi = B × A = 1.2 × 0.06 = 0.072 Wb
Φf = 0 → ΔΦ = 0.072 Wb
Φf = 0 → ΔΦ = 0.072 Wb
🔹 Step 4: Faraday’s Law
EMFavg = (N × ΔΦ) / Δt = (60 × 0.072) / 0.150 = 28.8 V
🎯 Final Answer:
The average induced EMF is 28.8 V.