Current Electri...

Two cells of emf $$E_1$$ and $$E_2$$ $$(E_1, > E_2)$$ are connected as shown in figure. When a potentiometer is connected between A and B, the balancing length of the potentiometer wire is 300cm. When the same potentiometer is connected between A and C, the balancing length is 100cm. The ratio of $$E_1$$ and $$E_2$$ is

Read the following statements carefully :
Y : The resistivity of a semiconductor decreases with increases of temperature.
Z : In a conducting solid, the rate of collision between free electrons and ions increases with
increase of temperature. Select the correct statement from the following :

In the figure, the potentiometer wire AB of length L and resistance $$9r$$ is joined to the cell D of emf $$\varepsilon  $$ and internal resistance r. The cell Cs emf is $$\epsilon  /2$$ and its internal resistance is $$2r$$. The galvanometer G will show no deflection when the length AJ is

In a potentiometer arrangement, a cell of emf 1.25 V gives a balance point at 35 cm length of the wire. If the cell is replaced by another cell, the balance point shifts to 63 cm, then emf of the second cell is

In a Wheatstone bridge, three resistances P, Q and R are connected in the three arms and the fourth arm is formed by two resistances $$S_1$$ and $$S_2$$ connected in parallel. The condition for the bridge to be balanced will be

Figure shows a potentiometer with a cell of 2.0 V and internal resistance 0.40$$\Omega$$ maintaining a potential drop across the resistor wire AB. A standard cell which maintains a constant emf of 1.02 V gives a balance point at 67.3 cm length of the wire. The standard cell is then replaced by a cell of unknown emf E and the balance point, similarly turns out to be at 82.3 cm, length of the wire. Then the E is

Potential gradient along AB is

In the potentiometer arrangement shown in figure, the driving cell D has emf E and internal resistance r. The cell C, whose emf is to measured, has emf $$\displaystyle \dfrac{E}{2}$$ and internal resistance 2r. The potentiometer wire is 100cm long. If balance is obtained, the length AJ is

How many positions are there on wire $$AB$$ such that on touching $$K$$ to those positions current from $$A$$ to $$B$$ remain same throughout if $$V>E$$ and internal resistance of primary circuit battery is zero?

If the filament of bulb D breaks then does bulb C give more light, less light, the same light or no light?