CUET · PHYSICS · PYQ PAPER 2023

A charged particle moves along a circle under the action of constant electric and magnetic fields. Which of the following is possible?

A E = 0B = 0
B E0, B = 0
C E = 0 B≠0
D \(E \neq 0, B \neq 0\)

Verified Solution

Answer & Solution

Correct Answer

(C) E = 0 B≠0

Step-by-step Solution

Detailed explanation

\( \vec{F}_{net} \cdot \vec{v} = 0 \) \( (q\vec{E} + q(\vec{v} \times \vec{B})) \cdot \vec{v} = 0 \) \( q\vec{E} \cdot \vec{v} = 0 \) For constant \( \vec{E} \) and circular motion (varying \( \vec{v} \)), \( \vec{E} = 0 \). Therefore, \( E=0, B \neq 0 \) is possible.

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

In the Block diagram of a generalised communication system, the elements are given below. The correct order of elements should be :
(A) Transmitter
(B) Information Source
(C) User of Information
(D) Channel
(E) Receiver
Choose the correct answer from the options given below:

CUET 2023 Easy

Match List-I with List-II

List-I (EM Waves)	List-II (Production)
(A) Infra-red rays	(I) Electrons in atoms emit light when they move from one energy level to a lower level
(B) Visible light rays	(II) Radioactive decay of the nucleus
(C) Ultraviolet rays	(III) Vibration of molecules
(D) Gamma rays	(IV) Inner shell electrons in atoms moving from one energy level to a lower level

Choose the correct answer from the options given below:

CUET 2025 Hard

Match List-I with List-I

List-I	List-II
A. Electric field outside a uniformly charged thin spherical shell	(I) zero
B. Electric field inside a uniformly charged thin spherical shell	(II) \(\frac{\lambda}{2 \pi \epsilon_0 r} \vec{n}\)
C. Electric field due to an infinitely long straight uniformly charged wire	(III) \(\frac{\sigma}{2 \epsilon_0} \vec{n}\)
D. Electric field due to a uniformly charged infinite plane sheet	(IV) \(\frac{k q}{r^2} \vec{r}\)

Choose the correct answer from the options given below:

CUET 2023 Medium

A current of 10 A in primary of a circuit is reduced to zero at a uniform rate in \( 10^{-3} \text{ s.} \) If coeff. of mutual inductance is 3 H, the induced emf in the secondary would be :

CUET 2023 Medium

Explore more questions on app

From CUET

Explore more questions on app

List-I	List-II
(A) \(l=m=n=\)	(I) 10
(B) \(k+l+m+n=\)	(II) 6
(C) \(k^2+l^2+(m-n)^2\)	(III) 2
(D) \(l^2+m^2+(n-k)=\)	(IV) 20