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Two tangent galvanometers A and B have coils of radii `8cm` and `16cm` respectively and resistance `8ohm` each. They are connected in parallel to a cell of emf `4V` and negligible internal resistance. The deflections produced are `30^@` and `60^@` respectivley. A has 2 turns. What is the number of turns in B? |
Answer» Here, `r_1=8cm, r_2=16cm`, `R_1=R_2=8ohm` `E=4V, theta_1=30^@, theta_2=60^@, n_1=2, n_2=?` `I=E/R=(2r_1H)/(mu_0n_1)tantheta_1=(2r_2H)/(mu_0n_2)=tan_2` `:. n_2=(n_1r_2tantheta_2)/(r_1tantheta_1)=(2xx16tan60^@)/(8tan30^@)=(4sqrt3)/(1//sqrt3)` `=12` |
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