Physics Questions and Answers

Which of the following particles conduct electricity through salty water?

Which of the following reduce(s) the effect of the back e.m.f. generated in the primary coil of an induction coil?

I. The capacitor in the circuit
II. The make and break contact in the circuit
III. The ratio of turns in the secondary to that in the primary

How long will it take to heat 3 kg of water from 28^oC to 88^oC in an electric taking a current of 6 A from an e.m.f. source of 220V?

A rectangular coil of wire can rotate in a magnetic field. The ends of the coil are soldered to the two halves of a split ring. Two carbon brushes are made to press lightly against the split ring and when these are connected in circuit with a battery and rheostat, the coil rotates. This is a description of

A cell of e.m.f. 1.5 V and internal resistance of 2.59 is connected in series with an ammeter of resistance 0.59 and a resistor of resistance 7.09. Calculate the current in the circuit.