AI Mentor

Check Your IQ

Free Expert Demo

Try Test

Courses

Dropper NEET Course Dropper JEE Course Class - 12 NEET Course Class - 12 JEE Course Class - 11 NEET Course Class - 11 JEE Course Class - 10 Foundation NEET Course Class - 10 Foundation JEE Course Class - 10 CBSE Course Class - 9 Foundation NEET Course Class - 9 Foundation JEE Course Class -9 CBSE Course Class - 8 CBSE Course Class - 7 CBSE Course Class - 6 CBSE Course

Offline Centres

A variable air capacitor used in radio tuning circuit is made of N semi-circular plates each of radius R and positioned a distance d from its neighboring plates. A second set of similar plates is enmeshed with its plates half-way between those of first set. Second set of plates can rotate as a complete unit. Determine the capacitance as a function of the angle of rotation θ, where θ = 0^∘ corresponds to the maximum capacitance.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

$\frac{(2 N - 1) ε_{0} (π - θ) R^{2}}{d}$

$\frac{{Nε}_{0} (π - θ) R^{2}}{d}$

$\frac{(N - 1) ε_{0} (π - θ) R^{2}}{d}$

$\frac{(N - 2) ε_{0} (π - θ) R^{2}}{d}$

answer is D.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

(4) when $θ = π$ then plates are out of mesh and overlap area is zero and when $θ = 0 º$ the overlap area is $\frac{{πR}^{2}}{2};$

By proportion effective overlap area of a single sheet is $\frac{(π - θ) R^{2}}{2}$ for angle $θ$ .

When there are two plates in combination, number of capacitors formed is 3. So, with N plates, number of capacitors is (2N–1).

So, total capacity is $C = \frac{(2 N - 1) ε_{0} A_{Active}}{Distance} = \frac{(2 N - 1) ε_{0} (π - θ) R^{2}}{d}$

Watch 3-min video & get full concept clarity

courses

No courses found

Result Producing online coaching for JEE/NEET of south India

Largest All India Test Series for JEE/NEET

Best Online Course for IIT JEE

Best Online Course for NEET

Best Online Course for CBSE

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Get Expert Academic Guidance – Connect with a Counselor Today!