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Moving Charges and Magnetism — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMoving Charges and Magnetism3 Marks
Question
Write the expression for the magnetic force acting on a charged particle moving with velocity n in the presence of magnetic field B. A neutron, an electron and an alpha particle moving with equal velocities, enter a uniform magnetic field going into the plane of the paper as shown. Trace their paths in the field and justify your answer.
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Answer

$\overrightarrow{\text{F}} = \text{q}(\overrightarrow{\text{v}}\times\overrightarrow{\text{B}})$
$\text{F}= \text{qvB}\sin\theta$ and Force (F) acts perpendicular to the plane containing $\overrightarrow{\text{v}} \text{and} \overrightarrow{\text{B}}$

Justification: Direction of force experienced by the particle will be according to the Fleming’s Left-hand rule.

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