Ten identical cells connected in series are needed to heat a wire of length one meter and radius ' r ' by 10∘C in time ' t '. How many cells will be required to heat the wirc of length two meter of the same radius by the same temperature in time 'r'?
Held on 30 Apr 2013 · Verified 9 Jul 2026.
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Two point charges +2μC and -2μC are placed 10 cm apart. The electric field at the midpoint is:
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