Exams › JEE Advanced › Physics
A thin stream of water normally bends toward a negatively charged rod brought near it. If instead a positively charged rod is brought near the stream, the stream will bend in which direction?
- Toward the rod, the same way it bent toward the negative rod
- Away from the rod, the opposite way
- It will not bend at all
- The behavior cannot be predicted
Correct answer: Toward the rod, the same way it bent toward the negative rod
Solution
Water molecules are polar. A charged rod (of either sign) polarizes the stream so that the near side acquires the opposite charge. The induced charge nearer the rod is always attracted, so the stream bends toward the rod whether the rod is positive or negative. Hence it bends the same way (toward the rod) as it did for the negative rod.
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