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Question
Two large metal sheets carry currents as shown in figure. The current through a strip of width dl is Kdl where K is a constant. Find the magnetic field at the points P, Q and R.
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Solution
At point P,
Current, i = 0
∴ Magnetic field B = 0
At point Q,
Applying Ampere's law, we get
`int B .dl = mu _0i`
`⇒ B .dl = mu _0 kdl`
`⇒ B= mu _0k`
At point R,
Current, i = 0
∴ B = 0
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