Physics · Moving Charges and Magnetic Field

JEE Main 2026 — 21 January, Morning Shift — Question 32

A current carrying is placed vertically and a particle of mass m with charge Q is released from rest. The particle moves along the axis of solenoid. If g is acceleration due to gravity then the acceleration (a) of the charged particle will satisfy :

  1. Option A:

    a=g\mathrm{a}=\mathrm{g}

    Correct
  2. Option B:

    a>g\mathrm{a}>\mathrm{g}

  3. Option C:

    a=0a=0

  4. Option D:

    0<0< a << g

Answer: A

Step-by-step solution

Since the solenoid is placed vertically, the magnetic field inside the solenoid will be either along - y or +y axis. ⇒ Particle will gain velocity along -y axis. ⇒F→B=q(v→×B→)\Rightarrow \quad \overrightarrow{\mathrm{F}}_{\mathrm{B}}=\mathrm{q}(\overrightarrow{\mathrm{v}} \times \overrightarrow{\mathrm{B}}) ⇒F→B=0\Rightarrow \quad \overrightarrow{\mathrm{F}}_{\mathrm{B}}=0 ⇒F→net =mg\Rightarrow \quad \overrightarrow{\mathrm{F}}_{\text {net }}=\mathrm{mg} ⇒anet =g\Rightarrow \quad \mathrm{a}_{\text {net }}=\mathrm{g}

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Physics
Chapter
Moving Charges and Magnetic Field
Topic
Motion of Charged Particles in magnetic Fields
A current carrying is placed vertically and a particle of mass m with… | JEE Main 2026 PYQ with Solution · DhiX AI