Advertisements
Advertisements
प्रश्न
If two resistors of 25 Ω and 15 Ω are joined together in series and then placed in parallel with a 40 Ω resistor, the effective resistance of the combination is :
(a) 0.1 Ω
(b) 10 Ω
(c) 20 Ω
(d)40 Ω
Advertisements
उत्तर
(c) 20 Ω
When 25 Ω and 15 Ω are connected in series, then:
Total resistance, R = 25 + 15 = 40 Î
This 40 Î is connected in parallel with the 40 Î resistor.
Therefore, the net resistance = 40 / 2 = 20 Î
APPEARS IN
संबंधित प्रश्न
Why is the series arrangement not used for domestic circuits?
Two resistors of 4Ω and 6 Ω are connected in parallel to a cell to draw 0.5 A current from the cell.
(i) Draw a labelled circuit diagram showing the above arrangement.
(ii) Calculate the current in each resistor. What is an Ohmic resistor?
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
The substance having infinitely high electrical resistance is called:
(a) conductor
(b) resistor
(c) superconductor
(d) insulator
What possible values of resultant resistance one can get by combining two resistances, one of value 2 ohm and the other 6 ohm?
A p.d. of 4 V is applied to two resistors of 6 Ω and 2 Ω connected in series. Calculate:
(a) the combined resistance
(b) the current flowing
(c) the p.d. across the 6 Ω resistor
Draw a V-I graph for a conductor at two different temperatures. What conclusion do you draw from your graph for the variation of resistance of conductor with temperature?
How will you oonnect five resistors, each of the value one ohm, to obtain an equivalent resistance of 0.2 `Omega`
Calculate the equivalent resistance of the following combination of resistor r1, r2, r3, and r4
Three resistors of 6.0 Ω, 2.0 Ω and 4.0 Ω are joined to an ammeter A and a cell of emf 6.0 V as shown in the following figure. Calculate :
- the effective resistance of the circuit.
- the reading of ammeter.
Choose the correct alternative and rewrite the following sentence.
If three resistors 2 ohms, 3 ohms and 4 ohms are connected in series, then the effective resistance in the circuit will be _______ ohms.
How does the resistivity of a semiconductor depend on temperature?
Calculate the quantity of heat that will be produced in a coil of resistance 75 Ω if a current of 2A is passed through it for 2 minutes.
Two resistors having 2Ω and 3Ω resistance are connected—(i) in series, and (ii) in parallel. Find the equivalent resistance in each case.
If R1 and R2 be the resistance of the filament of 40 W and 60 W respectively operating 220 V, then:
What is the maximum resistance which can be made using five resistors each of `1/5` W?
Two electric bulbs have resistances in the ratio 1 : 2. If they are joined in series, the energy consumed in them is in the ratio:
