Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
A long solenoid has 20 turns per cm. A small loop of area 4π cm2 is placed inside the solenoid normal to its axis. If the current carried by the solenoid changes steadily from 1.0 A to 3.0 A in 0.2 s, what is the magnitude of the induced emf in the loop while the current is changing?
PhysicsElectromagnetic InductionTS EAMCETTS EAMCET 2022 (18 Jul Shift 1)
Options:
  • A 2.4 μV
  • B 3.2 μV
  • C 7.2 μV
  • D 4.8 μV
Solution:
1963 Upvotes Verified Answer
The correct answer is: 3.2 μV

Magnetic field due to solenoid along its axis,

B=μ0nI=4π×10-720×102I=8π×10-4I T

Now induced EMF due to change in magnetic flux can be written as,

ε=ϕt=B2A-B1A0.2=5A8π×10-43-1=5×4π×10-416π×10-4=3.2 μV

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.