Advertisements
Advertisements
Question
Define the term resistivity and state its S.I. unit. Which will have higher resistivity a conductor or an insulator.
Solution
The resistivity of a substance is the resistance of a wire of that substance of unit length and unit area of cross-section. Its S. I. unit is ohm × m. An insulator will have higher resistivity.
APPEARS IN
RELATED QUESTIONS
Write any two characteristics of a series combination of resistors.
Find the equivalent resistance between points A and B.
What possible values of resultant resistance one can get by combining two resistances, one of value 2 ohm and the other 6 ohm?
Calculate the combined resistance in each case:
A graph is plotted taking p.d. along y-axis and electric current along x-axis. Name the physical quantity that represents the slope of this graph (Fig.).
What potential difference is needed to drive a current o f 1 A through a 5 Ω resistor?
2Ω resistor A, 1Ω resistor B and 4Ω resistor C are connected in parallel. The combination is connected across a 2V battery of negligible resistance. Draw the diagram of the arrangement and calculate:
(i) The current in each resistor A and C,
(ii) The current through battery.
Two resistors having 2Ω and 3Ω resistance are connected—(i) in series, and (ii) in parallel. Find the equivalent resistance in each case.
