Current electricity Questions
The power of an electric motor is 242 W when connected to a 220 V supply. When motor is operated at 200 V, the current drawn by it is
Seven resistors each of resistance R, are connected as shown in figure. The equivalent resistance between A and B is
Assertion (A): Meter bridge wire is generally made of constantan. Reason (R): Constantan has a very low thermal coefficient of resistance. In the light of the above statements, choose the most appropriate answer from the options given below.
Current density () at an area = (î + 4ĵ) mm² is given by = (2î + 3ĵ) A/m². The current through the area is
Equivalent resistance of the network between the terminals A and B is
An electric bulb rated 50 W – 200 V is connected across a 100 V supply. The power dissipation of the bulb is -
The value of unknown resistance (x) for which the potential between B and D will be zero in the arrangement shown, is :
A part of circuit is shown with wires A (copper), B and C (manganin). The currents in A, B, C are respectively:
A conducting wire of length l, area A, and resistivity ρ is connected to a battery. If the length is doubled and the area is halved, the resultant current would be: