Advertisements
Advertisements
प्रश्न
A piece of wire of resistance R is cut into three equal parts. These parts are then connected in parallel. If the equivalent resistance of this parallel combination is R1, what is the value of the ratio R1 : R?
Advertisements
उत्तर १
The resistance of each part is `"R"/3` Ω (as resistance is proportional to the length of the wire.)
`1/"R"_1 = 3/"R" + 3/"R" + 3/"R"`
`1/"R"_1= (3 + 3 + 3)/"R"`
`1/"R"_1= 9/"R"`
∴ `"R"_1 = "R"/9`
∴ `"R"_1/"R" = 1/9`
उत्तर २
The resistance of each part is `"R"/3` Ω (as resistance is proportional to the length of the wire.)
`1/"R"_1 = 3/"R" + 3/"R" + 3/"R"`
`1/"R"_1= (3 + 3 + 3)/"R"`
`1/"R"_1= 9/"R"`
∴ `1/"R"_1 = 9/"R"`
∴ `"R"/"R"_1 = 9`
APPEARS IN
संबंधित प्रश्न
Complete the following :-
(b)
A hot plate of an electric oven connected to a 220 V line has two resistance coils A and B, each of 24 Ω resistances, which may be used separately, in series, or in parallel. What are the currents in the three cases?
Are the lights in your house wired in series?
Four resistors each of resistance 2Ω are connected in parallel. What is the effective resistance?
An electrical appliance has a rating 100 W, 120V. The resistance of element of appliance when in use:
A given wire is stretched to double its length. How will its resistance change?
What connection is used in domestic appliances and why?
You are given four ammeters A, B, C and D having the least counts mentioned below:
(I) Ammeter A with least count 0.25 A
(II) Ammeter B with least count 0.5 A
(III) Ammeter C with least count 0.05 A
(IV) Ammeter D with least count 0.1 A
Which of the ammeters would you prefer for doing an experiment to determine the equivalent resistance of two resistances most accurately, when connected in parallel?
Two resistors of resistances 2 Ω and 3 Ω are connected in parallel to a cell to draw current 0.5 A from the cell. Draw a labelled diagram of the arrangement
