AB is a $$20$$ $$\Omega$$ resistor with a tapping point C that can be moved along AB. The resistances in AC, BC are proportional to the lengths AC, BC. Initially, C is at the mid-point of AB and the circuit is switched on.

If the tapping point C is moved so that the length BC is reduced to half its initial value, then the voltage across the $$15$$ $$\Omega$$ resistor,

 1 increases by $$1$$ V 2 decreases by $$1$$ V 3 increases by $$3$$ V 4 decreases by $$3$$ V

Subtopic: Â Kirchoff's Voltage Law |
From NCERT
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The current flowing through the left $$20~\Omega$$ resistor is:

 1 $$1$$ A 2 $$0.5$$ A 3 $$2.5$$ A 4 $$3$$ A
Subtopic: Â Kirchoff's Voltage Law |
Â 56%
From NCERT
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All the cells, shown in the figure below, are of $$2$$ V, and all the resistances are $$1$$ $$\Omega$$. When a potential difference $$V$$ is applied between A and B, the current through the circuit doubles compared to the situation when the potential difference is made zero.
Then,

 1 $$V=2$$ volt, positive at A. 2 $$V=2$$ volt, negative at A. 3 $$V=6$$ volt, positive at A. 4 $$V=6$$ volt, negative at A.

Subtopic: Â Kirchoff's Voltage Law |
From NCERT