A current is passed through two coils connected in series. The potential difference across the first coil is 3 volts and that of the second coil 4.5 volts. If the first coil has resistance of 2 ohm, the resistance of the second coil is:

A 4Ω resistor in series with 8Ωresistance are connected to 12 V supply.If another resistor of 8Ω is connected across the 8Ω resistor the current drawn from source would be

A maximum current 0.5mA can be passed through a galvanometer of resistance 20Ω.The resistance to be connected in series to convert it into voltmeter of range 0-5V is

The cold junction of a thermocouple is at 0⁰ C,The thermo e.m.f produced in the thermocouple is given by the equation E=16T-0.04T²V , where T is the temperature of the hot junction.The temperature of inversion and neutral temperature of the thermo couple are

Thermo emf produce per 1⁰C temperature difference between the junction is 0.005V.when cold junction is at 10⁰C,and hot junction is at t⁰C,thermo emf produced is 0.5 V.,The value of t is

In a meterbridge experiment,the balance length is 40cm.the resistance in the gap opposite to this length of wire is 8 ohm.The resistance in the other gap is

A 25 watt,220 volt bulb and a 100 watt,220 volt bulb are connected in series across 440 volt line

A potentiometer having wire of 4m length is connected to the terminals of a battery with a steady voltage.A leclanche cell has a null points at 1m,If the length of the potentiometer wire is increased by 1m,the position of the null points is

The emf of a Cu-Fe thermocouple varies with the temperature T of the hot junction, the cold junction being at 10⁰C, as V_inμv=14T-0.02T².Determinate the neutral temperature and the of inversion.

While connecting 6 cells in a battery in series,ina tape recorder,by mistake one cell is connected with reverse polarity.If the effective resistance of load is 24 ohm and internal resistance of each cell is one ohm and emf 1.5V,the current delivered by the battery is