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
A. Zero
B. \(\frac{\mathrm{B} v \pi \mathrm{r}^{2}}{2}\) and P is at higher potential
C. πrBυ and k is at higher potential
D. 2rBυ and R is at higher potential
Answer:D
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
A. Zero B. \(\frac{\mathrm{B} v \pi \mathrm{r}^{2}}{2}\) and P is at higher potential C. πrBυ and k is at higher potential D. 2rBυ and R is at higher potential