The unit of reduction factor of tangent galvanometer is

The number of turns and radius of cross-section of the coil of a tangent galvanometer are doubled. The reduction factor $K $ will be

The needle of a deflection galvanometer shows a deflection of $60^o $ due to a short bar magnet at a certain distance in $\tan A$ position. If the distance is doubled, the deflection is

Two tangent galvanometers having coils of the same radius are connected in series. A current flowing in them produces deflections of $60° $ and $45°$  respectively. The ratio of the number of turns in the coils is

The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is $2 \,s. $ The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together. The time period of this combination will be