JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A charge of \(4.0 \mu \mathrm{C}\) is moving with a velocity of \(4.0 \times 10^6 \mathrm{~ms}^{-1}\) along the positive \(\mathrm{y}\)-axis under a magnetic field \(\vec{B}\) of strength \((2 \hat{k})\ T\). The force acting on the charge is \(x \hat{i} N\). The value of \(x\) is _______.
- A \(12\)
- B \(78\)
- C \(85\)
- D \(32\)
Answer & Solution
Correct Answer
(D) \(32\)
Step-by-step Solution
Detailed explanation
\(\mathrm{q} =4 \mu \mathrm{C}, \overrightarrow{\mathrm{v}}=4 \times 10^6\) \( \hat{\mathrm{j}} \mathrm{m} / \mathrm{s} \) \(\overrightarrow{\mathrm{B}} =2 \hat{\mathrm{k}} \mathrm{T} \)…
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