Godfrey Classic Prince
Last Activity: 13 Years ago
Dear keshav kr,
Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points, and inversely proportional to the resistance between them.
The mathematical equation that describes this relationship is:

where I is the current through the conductor in units of amperes, V is the potential difference measured across the conductor in units of volts, and R is the resistance of the conductor in units of ohms.
Rheostat is basically a variable resistance. we connect it in the circuit if we want to change the resistance of the circuit. it has a sliding nob which is one of the terminal of this resistor and which can slide on the cylindrically wounded coil. one end of this wounded coil is connected to the circuit & other end is left free. resistance of the circuit can be changed by varying the nob over the wounded coil, so rheostat is not a tough device but a simple variable reistor.

Hope this helped you immensely...
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