Two tangent galvanometers have circular coils of same radii differing only in the number of turns. They are connected in series. WHen a a steady current is passed in the circuit, the mean deflections of galvanometer are `theta_1` and `theta_2`. deduce an expression for the ratio of number of turns of the galvanometer.

A galvanometer having a coil resistance of 100 omega gives a full scale deflection , when a current of 1 mA is passed through it. The value of the resistance, which can convert this galvanometer into ammeter giving a full scale deflection for a current of 10A.

A long wire is first bent into a circular coil of one turn and then into a circular coil of smaller radius, having n identical turns. If the same current passes in both the cases, find the ratio of the magnetric fields produced at the centre in the two cases.

A galvanometer having a coil resistance of 60 Omega shows full scale defection when a current of 1.0 A passes thoguth it. It can vbe convered into an ammeter to read currents up to 5.0 A by

The magnetic field of a given length of wire carrying a current of a single turn circular coil at centre is B, then its value for two turns for the same wire when same current passing through it is

An electric current is passed through a circuit containing two wires of the same material, connected in parallel. If the lengths and radii are in the ratio of 4/3 and 2/3, then the ratio of the current passing through the wires will be

For a circular coil of radius R and N turns carrying current I, the magnitude of the magnetic field at a point on its axis at a distance x from its centre is given by, B= (mu_0IR^2N)/(2(x^2+R^2)^(3/2)) . Consider two parallel co-axial circular coils of equal radius R, and number of turns N, carrying equal currents in the same direction, and separated by a distance R. Show that the field on the axis around the mid-point between the coils is uniform over a distance that is small as compared to R, and is given by, B=0.72 (mu_0NI)/R approximately.

A galvanometer, together with an unknown resistance in series, is connected across two identical batteries of each 1.5 V. When the batteries are connected in series,the galvanometer records a current of 1 A, and when the batteries are connected in parallel, the current is 0.6 A. In this case, the internal resistance of the battery

In a potentiometer, a standard cell of emf 5V and of negligible resistance maintains a steady current through the galvanometer wire of length 5 m. Two primary cells of emfs epsilon_(1) and epsilon_(2) are joined in series with (i) same polarity and (ii) apposite polarity.The combination is connected through it galvanometer and a joined to the potentiometer. The balancing length is the two cases are found to be 350 cm and 50 cm respectively Draw the necessary circuit diagram.

In a potentiometer, a standard cell of emf 5V and of negligible resistance maintains a steady current through the galvanometer wire of length 5 m. Two primary cells of emfs epsilon_(1) and epsilon_(2) are joined in series with (i) same polarity and (ii) apposite polarity.The combination is connected through it galvanometer and a joined to the potentiometer. The balancing length is the two cases are found to be 350 cm and 50 cm respectively Find the value of emfs of the two cells