Magnetic Effects & Magnetism

JEE Main level, single correct, medium

189 of 276

Question 189 of 276

Consider a moving coil galvanomenter (MCG):
A. The torsional constant in moving coil galvanometer has dimentions [ML2 T−2]\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]
B. Increasing the current sensitivity may not necessarily increase the voltage sensitivity.
C. If we increase number of turns (N)(\mathrm{N}) to its double (2 N)(2 \mathrm{~N}), then the voltage sensitivity doubles.
D. MCG can be converted into an ammeter by introducing a shunt resistance of large value in parallel with galvanometer.
E. Current sensitivity of MCG depends inversely on number of turns of coil.

Choose the correct answer from the options given below:

Show answer and solution

Answer: (D) A, B Only

(A) τ=Cθ⇒[ML2 T−2]=[C][1]\tau=\mathrm{C} \theta \Rightarrow\left[\mathrm{ML}^2 \mathrm{~T}^{-2}\right]=[\mathrm{C}][1]
(B) C.S=θI=BNAC\mathbf{C} . \mathrm{S}=\frac{\theta}{\mathrm{I}}=\frac{\mathrm{BNA}}{\mathrm{C}};
V.S. =BNARC[R=\frac{\mathrm{BNA}}{\mathrm{RC}}[\mathrm{R} also depends on ' N ']
(C) V.S. ∝NABCRR→NR\propto \frac{\mathrm{NAB}}{\mathrm{CR}} \quad \mathrm{R} \rightarrow \mathrm{NR}
(D) False [Theory]
(E) E [False]
C.S∝ N\mathrm{C} . \mathrm{S} \propto \mathrm{~N}
⇒∵C.S.=NABC\Rightarrow \because \mathrm{C} . \mathrm{S} .=\frac{\mathrm{NAB}}{\mathrm{C}}

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.

More Physics practice

JEE Main Physics practice question on Magnetic Effects & Magnetism (Force and Torque on Current Carrying Conductor), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.