Advertisements
Advertisements
प्रश्न
Two resistors having resistance 8 Ω and 12 Ω are connected in parallel. Find their equivalent resistance.
उत्तर
Let R be the equivalent resistance
∴ `1/"R" = 1/"R"_1 + 1/"R"_2`
`1/"R" = 1/8 + 1/12`
= `(3 +2)/24`
`1/"R" = 5/24`
R = `24/5`
= 4.8 Ω
or R = `("R"_1"R"_2)/("R"_1 + "R"_2)`
= `(8 xx 12)/((8 + 12))`
= 4.8 Ω
संबंधित प्रश्न
How many 176 Ω resistors (in parallel) are required to carry 5 A on a 220 V line?
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?
A resistor has a resistance of 176 ohms. How many of these resistors should be connected in parallel so that their combination draws a current of 5 amperes from a 220 volt supply line?
A wire of resistance R1 is cut into five equal pieces. These five pieces of wire are then connected in parallel. If the resultant resistance of this combination be R2, then the ratio `R_1/R_2` is:
(a) `1/25`
(b)1/5
(c)5
(c)25
Two resistances when connected in parallel give resultant value of 2 ohm; when connected in series the value becomes 9 ohm. Calculate the value of each resistance.
A battery of e.m.f 16 V and internal resistance 2 Ω is connected to two resistors 3Ω and 6Ω connected in parallel. Find:
- the current through the battery.
- p.d. between the terminals of the battery,
- the current in 3 Ω resistors,
- the current in 6 Ω resistor.
Two resistors when connected in parallel give the resultant resistance of 2 ohms, but when connected in series the effective resistance becomes 9 ohms. Calculate the value of each resistance.
Two devices are connected between two points say A and B in parallel. The physical quantity that will remain the same between the two points is:
Two resistors of resistance 2 Ω and 3 Ω are connected in parallel to a cell to draw current 0.5 A from the cell. Calculate the current in each resistor.