Advertisements
Advertisements
Question
A particular resistance wire has a resistance of 3 ohm per meter. Find the potential difference of the battery which gives a current of 2 A in each of the 1.5 m length when connected in the parallel to the battery (assume that resistance of the battery is negligible).
Advertisements
Solution
A current of 2.0 A flows via each of the parallel-connected wires.
Resistance of 1 m wire = 3.0 Ω
Resistance of 1.5 m wire = 3 × 1.5 = 4.5 Ω
I = 2 A
V = IR
= 2 × 4.5
= 9 V
APPEARS IN
RELATED QUESTIONS
The equivalent resistance of the parallel combination of two resistors of 60Ω and 40Ω is _______.
A) 24Ω
(B) 100Ω
(C) 50 Ω
(D) 240Ω
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
Show with the help of diagrams, how you would connect three resistors each of resistance 6 Ω, so that the combination has resistance of (i) 9 Ω (ii) 4 Ω.
Two exactly similar electric lamps are arranged (i) in parallel, and (ii) in series. If the parallel and series combination of lamps are connected to 220 V supply line one by one, what will be the ratio of electric power consumed by them?
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.
In the figure below, the ammeter A reads 0.3 A. Calculate:
(i) the total resistance of the circuit
(ii) the value of R
(iii) the current flowing through R.
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?
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.
