JEE Mains · Physics · STD 12 - 1. Electric charges and fields
A point charge \(q =1 \mu C\) is located at a distance 2 cm from one end of a thin insulating wire of length 10 cm having a charge \(Q=24 \mu C\), distributed uniformly along its length, as shown in figure. Force between q and wire is _________ N.
(Use \(\frac{1}{4 \pi \epsilon_0}=9 \times 10^9 N \cdot m ^2 / C ^2\) )
- A 45
- B 90
- C 180
- D 60
Answer & Solution
Correct Answer
(B) 90
Step-by-step Solution
Detailed explanation
\(F =\int dF =\int_{2 cm}^{12 cm} \frac{ kq \lambda dx }{ x ^2}= kq \lambda\left(\frac{1}{2 \times 10^{-2}}-\frac{1}{12 \times 10^{-2}}\right)\)…
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