A potential difference $V$ is applied across a conductor of length $L$ and diameter $D .$ How is the resistance $R$ of the conductor affected, when in turn $(i)$ $V$ is halved $(ii)$ $L$ is halved and $(iii)$ $D$ is doubled ? Justify your answer in each case.
A potential difference $V$ is applied across a conductor of length $L$ and diameter $D .$ How is the resistance $R$ of the conductor affected, when in turn $(i)$ $V$ is halved $(ii)$ $L$ is halved and $(iii)$ $D$ is doubled ? Justify your answer in each case.
The table below gives the variation
| $V$ is halved | $L$ is halved | $D$ is doubled | |
| $R =\frac{\rho L }{ A }$ | No change | $R$ is halved | $R$ becomes one$-$fourth |
Similar Questions
Read the following statements carefully and write whether the statement is true or false
$(i)$ The quantity of charge flowing past a point multiplied by time is current.
$(ii)$ The flow of charge through a conducting wire connected to a cell is the result of chemical reaction inside the cell
$(iii)$ The resistivity of all pure metals increases with increase in temperature.
$(iv)$ Ohm's law is a relation between the power used in a circuit to the current and the potential difference.
$(v)$ $A$ series circuit has only one conducting path for the electrons that move through it; a parallel circuit has multiple conducting paths.
$(vi)$ A conducting wire offers resistance to the flow of electrons because electrons repel each other in the wire.
Read the following statements carefully and write whether the statement is true or false
$(i)$ The quantity of charge flowing past a point multiplied by time is current.
$(ii)$ The flow of charge through a conducting wire connected to a cell is the result of chemical reaction inside the cell
$(iii)$ The resistivity of all pure metals increases with increase in temperature.
$(iv)$ Ohm's law is a relation between the power used in a circuit to the current and the potential difference.
$(v)$ $A$ series circuit has only one conducting path for the electrons that move through it; a parallel circuit has multiple conducting paths.
$(vi)$ A conducting wire offers resistance to the flow of electrons because electrons repel each other in the wire.
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