The tangent galvanometers having coils of the same radius are connected in series. A current flowing in them produces deflections of 600& 450 respectively. The ratio of the number of turns in the coil is

In the first galvanometer  i1=K1tanθ1                                                   i1=K1tan600=3K1In the second galvanometer   i2=K2tanθ2                                                i2=K2tan450=K2In series combination  i1=i2 ∴3K1=K2 ⇒K1K2=13But  K∝1n ⇒K1K2=n2n1⇒n1n2=K2K1=31