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Question
A 10-cm long rod carries a charge of +50 μC distributed uniformly along its length. Find the magnitude of the electric field at a point 10 cm from both ends of the rod.
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Solution
E = `(2"k"λ)/("r")sin θ/2`
`sin θ/2 = 5/10 = 1/2`
`θ/2 = 30`
E = `2 xx 9 xx 10^9 xx 50/0.10 xx 1/2 xx sqrt(100 - 25)`
E = `2 xx 9 xx 10^9 xx 50/0.10 xx 1/2 xx sqrt75`
E = `2 xx 9 xx 10^9 xx 50/0.10 xx 1/2 xx 5sqrt3`
E = 5.2 × 107 V/m
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