Advertisements
Advertisements
प्रश्न
What is a resistance? Define it with respect to Ohm’s law,
Advertisements
उत्तर
In the flow of current in a conductor, electrons are drifted. During this drift or flow, electrons mutually collide against each other and the atoms of the conductor. These collisions give rise to some obstruction to the flow of electrons. This opposition or obstruction offered by a conductor to the flow of electrons is called ‘Resistance’. According to Ohm’s law, the ratio between potential difference V and the current i, is a constant provided the temperature and physical conditions of the conductor remain unaltered. As such the ratio V/I is called the resistance, i.e., ‘Ohmic resistance’ of the conductor.
संबंधित प्रश्न
Two resistors of 4Ω and 6 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
(i) Draw a labelled circuit diagram showing the above arrangement.
(ii) Calculate the current in each resistor. What is an Ohmic resistor?
Find the equivalent resistance between A and B

How does the resistance of a wire change when:
its length is tripled?
State how are the two resistors joined with a battery when equivalent resistance is more than either of the two resistances.
State expression for Resistance connected in series.
State expression for Cells connected in parallel.
Six equal resistors of 1 ohm each are connected to form the sides of a hexagon ABCDEF. Calculate the resistance offered by the combination if the current enters at A and leaves it at D.
Two wires of the same length and area made of two materials of resistivity ρ1 and ρ2 are connected in series to a source of potential V. The equivalent resistivity for the same area is:
What is the maximum resistance which can be made using five resistors each of `1/5` W?
