If the magnetic flux through a coil changes from 0.5 Wb to 0.2 Wb in 2 seconds,
Practice Questions
Q1
If the magnetic flux through a coil changes from 0.5 Wb to 0.2 Wb in 2 seconds, what is the average induced emf? (2023)
150 V
100 V
75 V
50 V
Questions & Step-by-Step Solutions
If the magnetic flux through a coil changes from 0.5 Wb to 0.2 Wb in 2 seconds, what is the average induced emf? (2023)
Step 1: Identify the initial magnetic flux (Φ_initial) and the final magnetic flux (Φ_final). Here, Φ_initial = 0.5 Wb and Φ_final = 0.2 Wb.
Step 2: Calculate the change in magnetic flux (ΔΦ) using the formula ΔΦ = Φ_final - Φ_initial. So, ΔΦ = 0.2 Wb - 0.5 Wb = -0.3 Wb.
Step 3: Identify the time interval (Δt) over which the change occurs. Here, Δt = 2 seconds.
Step 4: Use the formula for average induced emf (ε) which is ε = -ΔΦ/Δt. Substitute the values: ε = -(-0.3 Wb) / 2 seconds.
Step 5: Calculate the average induced emf: ε = 0.3 Wb / 2 = 0.15 V.
Step 6: Convert the average induced emf to volts: 0.15 V = 150 V (since 1 V = 100 mV).
Faraday's Law of Electromagnetic Induction – This law states that the induced electromotive force (emf) in a closed circuit is proportional to the rate of change of magnetic flux through the circuit.
Magnetic Flux – Magnetic flux is the product of the magnetic field and the area through which it passes, and it is measured in Webers (Wb).
Average Induced EMF – The average induced emf can be calculated using the formula: average induced emf = -ΔΦ/Δt, where ΔΦ is the change in magnetic flux and Δt is the change in time.
