1please anyone ??
A charge Q is placed at each of the opposite corners of a square . A charge q is place at each of the other two corners. If net electrical force on Q is zero then Q/q equals :
a) -2√2 B) -1 C) 1 D ) -1/√2
ans.............> (a)
please give me solution with explanation please ??
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9 Answers
39Okay ab answer aa jaayega..I wasn't thinking in terms of vectors. Silly of me. F3 can be resolved into components where obviously it makes angles of 45 degrees with both X and Y axes.
F_{Q} = (F_{1} + F_{3}cos45) + (F_{2} + F_{3}sin45) = 2.\frac{kQ.q}{a^2} + \frac{kQ^2}{2a^2}(\sqrt{2}) = 0 => 2Q.q + \frac{Q^2}{\sqrt{2}} = 0 => \frac{Q}{q} = \frac{-2}{\sqrt{2}}
The other root of that equation would be Q = 0, which is not possible.
1hmm. that was easy.
Why didn't i get the answer. Probably ab IIT ke bad AIEEE bhi gaya samjho.
ANYWAYS thnks Pritish.
39Mera bhi answer nahi aa raha tha. I didn't make the diagram. So don't worry, you're not the only one lagging behind. Just keep calm...even my JEE sucked. Atleast we can try to redeem ourselves in AIEEE, BITS, etc. We can't give up.
1Hey! don u think the options u hv mentioned don match wid the question paper
Q.9. A charge Q is placed at each of the opposite corners of a square. A charge q is placed at each of the other two corners. If the net electric force on Q is zero, then Q/q equals:
1. -1/√2
2. -2√2
3. -1
4. 1
Ans: -2√2
http://www.fiitjee.com/down/aieeesuccesscheck09.pdf
Ques.20
1ya just interchangedchanged the options that's it. nothing less or more [1]