Advertisements
Advertisements
Question
Name the material of wire used for making standard resistances. Give a reason.
Advertisements
Solution
Constantan is used for making standard resistances. The reason is that its resistance remains almost unaffected with change in temperature.
RELATED QUESTIONS
Judge the equivalent resistance when the following are connected in parallel − (a) 1 Ω and 106Ω, (b) 1 Ω and 103Ω and 106Ω.
The V-I graph for a series combination and for a parallel combination of two resistors is shown in the figure below. Which of the two A or B. represents the parallel combination? Give reasons for your answer.

An electrical appliance has a resistance of 25 Ω. When this electrical appliance is connected to a 230 V supply line, the current passing through it will be:
(a) 0.92 A
(b) 2.9 A
(c) 9.2 A
(d) 92 A
What possible values of resultant resistance one can get by combining two resistances, one of value 2 ohm and the other 6 ohm?
In series combination of resistances ______.
What is the equivalent resistance between A and B in the given circuit (Fig?)

Calculate the equivalent resistance between the points A and B for the following combination of resistors:
Two resistors of 4Ω and 6Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
Draw a labelled circuit diagram showing the above arrangement.
What should be the length of a nickel wire of area of cross-section 3 mm2 used for making a rheostat of 750 ohm? (ρ of nickle = 0.069 Ohm mm2/m)
The resistance of two resistors joined in series is 8Ω and in parallel is 1.5Ω. Find the value of the two resistances.
