Advertisements
Advertisements
प्रश्न
You have three resistors of values 2Ω, 3Ω and 5Ω. How will you join them so that the total resistance is less than 1Ω? Draw diagram and find the total resistance.
Advertisements
उत्तर
The three resistors should be connected in parallel
To get a total resistance less than 1Ω
In parallel, if the equivalent resistance is RP, then
`therefore 1/R_p = 1/R_1 + 1/R_2 + 1/R_3`
`therefore 1/R_p =1/2+1/3+1/5`
`therefore 1/R_p = (15+10+6)/30`
`therefore 1/R_p = 31/30`
⇒ `R_p = 30/31 = 0.97 Ω`
संबंधित प्रश्न
Complete the following :-
(b)
Show how you would connect two 4 ohm resistors to produce a combined resistance of (a) 2 ohms (b) 8 ohms.
Explain with diagram what is meant by the "series combination" and "parallel combination" of resistances. In which case the resultant resistance is : (i) less, and (ii) more, than either of the individual resistances?
If current flows through two lamps arranged:
(a) in series,
(b) in parallel,
and the filament of one lamps breaks, what happens to the other lamp? Explain your answer.
In parallel combination of resistances ______.
Two resistors having resistance 4𝛀 and 6𝛀 are connected in parallel. Find their equivalent resistance.
A cell supplies a current of 1.2 A through two 2Ω resistors connected in parallel. When the resistors are connected in series, if supplies a current of 0.4 A. Calculate the internal resistance and e.m.f of the cell.
What connection is used in domestic appliances and why?
A piece of wire having a resistance R is cut into five equal parts.
- How will the resistance of each part of the wire change compared with the original resistance?
- If the five parts of the wire are placed in parallel, how will the resistance of the combination change?
- What will be ratio of the effective resistance in series connection to that of the parallel connection?
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?
