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प्रश्न
A thin semi-circular conducting ring (PQR) of radius r is falling with its plane vertical in a horizontal magnetic field B, as shown in the figure.
The potential difference developed across the ring when its speed v , is
विकल्प
Zero
`("Bv"pi"r"^2)/2` and P is at higher potential
πrBv and R is at higher potential
2rBv and R is at higher potential
उत्तर
2rBv and R is at higher potential
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