Current Electri...

Four conductors of resistance 4, 3, 9 and 6 ohm are connected in AB,BC, CD and DA arms of a Wheatstone bridge. The bridge can be balanced by connecting.

A cell of emf 2 V and negligible resistance is connected in series with a resistance of 5 ohm, and a potentiometer wire of resistance 10 ohm. The potential drop per cm if the length of the potentiometer wire is 10 m. The emf of cell which is balanced by 750 cm long wire is :

In a potentiometer using two cells in series gives a balance length of $$600cm$$. When the same cells are connected opposing each other then balance length is $$100cm$$. The ratio of emf of larger to smaller cell is:

In a potentiometer, the balance length with standard cadmium cell is 509 cm. The emf of a cell which when connected in the place of the standard cell gave a balanced length of 750 cm is (emf of the standard cell is 1.018V):

A 5$$^{0}$$C rise is temperature is observed in a conductor by passing a current, when the current is doubled, the rise in temperature will be nearly

A,B,C and D are four coils of wires of 2, 2, 2 and 3 ohm resistances respectively and are arranged to form a Wheatstone bridge.The resistance which the coil 'D' must be shunted in order that the bridge may be balanced is:

A battery has four cells in parallel, each has an e.m.f $$1.5V$$ and internal resistance $$0.8 \Omega$$. The current delivered by it to a load of $$2.8 \Omega$$ is

Two batteries of different emf and internal resistances connected in series with each other and with an external load resistor. The current is 3.0 A. When the polarity of one battery is reversed, the current becomes 1.0 A. The ratio of the emf of the two batteries is :

In a potentiometer whose wir   e resistance is 10$$\Omega $$ the potential fall per cm is V volts. To reduce it to V/4  Volt cm$$^{-1}$$, the resistance that must be connected in series with the potentiometer wire is

Three unequal resistors in parallel are equivalent to a resistance $$1\ \Omega$$. If two of them are in the ratio $$1 : 2$$ and if no resistance value is fractional, the largest of the three resistances in $$\Omega$$ is: