Advertisements
Advertisements
प्रश्न
In the following figure calculate:
- the total resistance of the circuit
- the value of R, and
- the current flowing in R.
Advertisements
उत्तर
(a) V = 4 V; I = 0.4 A
Total Resistance R'=?
R' = `"V"/"I" = 4/0.4` = 10 Ω
(b) R1 = 20 Ω; R' = 10 Ω
`1/"R'" = 1/"R" + 1/"R"_1`
`1/10 = 1/"R" + 1/20`
`1/"R" = 1/10 - 1/20`
`1/"R" = (2 - 1)/20`
`1/"R" = 1/20`
R = 20 Ω
(c) R = 20 ohm; V = 4 V
I = `"V"/"R" = 4/20` = 0.2 A
APPEARS IN
संबंधित प्रश्न
An electric lamp of 100 Ω, a toaster of resistance 50 Ω, and a water filter of resistance 500 Ω are connected in parallel to a 220 V source. What is the resistance of an electric iron connected to the same source that takes as much current as all three appliances, and what is the current through it?
What are the advantages of connecting electrical devices in parallel with the battery instead of connecting them in series?
Show how you would connect three resistors, each of resistance 6 Ω, so that the combination has a resistance of 9 Ω.
Several electric bulbs designed to be used on a 220 V electric supply line are rated 10 W. How many lamps can be connected in parallel with each other across the two wires of 220 V line if the maximum allowable current is 5 A?
Are the lights in your house wired in series?
Which of the following combinations have the same equivalent resistance between X and Y?
Calculate the equivalent resistance between the points A and B in Fig. if each resistance is 2·0 Ω.
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.
Explain, why is the p.d. between the terminals of a storage battery less when it is supplying current than when it is on open circuit. A battery of e.m.f. 10 volts and internal resistance 2.5 ohms has two resistances of 50 ohms each connected to it. Calculate the power dissipated in each resistance
(a) When they are in series,
(b) When they are in parallel.
In each case calculate the power dissipated in the battery.
A current of 2 A is passed through a coil of resistance 75 Ω for 2 minutes.
(a) How much heat energy is produced?
(b) How much charge is passed through the resistance?
