CUET · PHYSICS · PYQ PAPER 2025

Figure shows a rectangular conductor PQRS in which the conductor PQ is free to move. The conductor PQ is moved towards the left with a constant velocity V as shown in the figure. Assume that there is no loss of energy due to friction. What will be the magnetic flux linked with the loop PQRS and the motional emf?

A Magnetic \( flux = Bl(xV) \); Motional \( emf = Blx \)
B Magnetic \( flux = Blx \); Motional \( emf = (BlV)/t \)
C Magnetic flux = Blx: Motional emf = BlV
D Magnetic flux \(=B /(l x)\); Motional \( emf = BlV \)

Verified Solution

Answer & Solution

Correct Answer

(C) Magnetic flux = Blx: Motional emf = BlV

Step-by-step Solution

Detailed explanation

Magnetic flux \( \Phi_B = B \times (\text{Area}) = B(lx) = Blx \) Motional emf \( \epsilon = \left| \frac{d\Phi_B}{dt} \right| = \left| \frac{d(Blx)}{dt} \right| = \left| Bl \frac{dx}{dt} \right| \) Since \( \left| \frac{dx}{dt} \right| = V \), \( \epsilon = BlV \)

Apply the relevant identity from the chapter and substitute the values established in the previous step, keeping the original constraint in view.

Use the simplified expression to isolate the unknown, then plug the result back into the question setup to confirm the working is internally consistent.

Cross-check against a boundary or limiting case. Both the dimensional balance and the qualitative behaviour at the extreme should agree with the candidate answer.

Combine the steps above to identify the correct option. The remaining choices each fail at least one of the consistency, dimensional, or boundary checks.

Same subject

Explore more questions on app

From CUET

Explore more questions on app

List-I (Ligands)	List-II (Examples)
(A). Ambidentate	(I). thiocyanato
(B). Unidentate	(II). water
(C). Didentate	(III). oxalate
(D). Polydentate	(IV). ethylenediaminetetraacetate