JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Given below are two statements: One is labelled as Assertion \((A)\) and the other is labelled as Reason \((R).\) Assertion \((A)\) : In an uniform magnetic field, speed and energy remains the same for a moving charged particle. Reason \((R)\) : Moving charged particle experiences magnetic force perpendicular to its direction of motion.
- A Both \((A)\) and \((R)\) are true and \((R)\) is the correct explanation of \(( A )\)
- B Both \((A)\) and \((R)\) are true but \((R)\) is NOT the correct explanation of \(( A )\)
- C \((A)\) is true but \((R)\) is false
- D \((A)\) is false but \((R)\) is true.
Answer & Solution
Correct Answer
(A) Both \((A)\) and \((R)\) are true and \((R)\) is the correct explanation of \(( A )\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ F }= q (\overrightarrow{ v } \times \overrightarrow{ B })\) \(\overrightarrow{ F } \perp \overrightarrow{ V }\) Work done \(=\overrightarrow{ F } \cdot \overrightarrow{ S }\) Work done \(=0\)
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