Advertisements
Advertisements
Question
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.
Advertisements
Solution
E.m.f. of battery E = 16V, r = 2Ω
Effective resistance of 3Ω and 6Ω connected in parallel R is
`1/"R" = 1/3 + 1/6`
= `3/6`
= `1/2`
∴ R = 2Ω
Total resistance = (R + r)
= (2 +2)
= 4Ω
(a) Current through battery
I = `"V"/("R" + r) = "E"/("R" +r)`
I = `(16V)/(4Ω)`
= 4 A
(b) p.d between terminal of battery
V = IR
= 4 × 2
= 8V
(c) The current in 3Ω resistor
I1 = `"V"/"R"`
= `8/3`
= 2.66 A
(d) The current in 6Ω resistor
I2 = `"V"/"R"`
= `8/6`
= 1.34 A
APPEARS IN
RELATED QUESTIONS
Complete the following :-
(c)
Two resistors, with resistance 5 Ω and 10 Ω respectively are to be connected to a battery of emf 6 V so as to obtain:
(i) minimum current flowing
(ii) maximum current flowing
(a) How will you connect the resistances in each case?
(b) Calculate the strength of the total current in the circuit in the two cases.
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
You are given three resistances of 1, 2 and 3 ohms. Shows by diagrams, how with the help of these resistances you can get:
(i) 6 Ω
(ii) `6/1` Ω
(iii) 1.5 Ω
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.
What is the equivalent resistance of 5 equal resistors, each of value 2`Omega` 1 when oonnected in (a) Series ( b) ParaIleI?
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.
State the S.I. unit of electrical resistance and define it.
The least resistance obtained by using 2 Ω, 4 Ω, 1 Ω and 100 Ω is:
A particular resistance wire has a resistance of 3·0 ohm per metre. Find the resistance of 5 m length of a wire of the same material, but with twice the area of cross section.
