Advertisements
Advertisements
प्रश्न
The voltage across a 3Ω resistance is 6 V. How large is the current? What is
the resistance of a filament lamp when a voltage of 3 V across it causes a
current of 0.5 A?
Advertisements
उत्तर
If voltage, V = 6 volt and resistance R = 3Ω
The a/c to ohm's law, current I = `"V"/"R" = 6/3 = 2 "A"`
For filament lamp:
Given that, voltage= 3 V, current= 0.5 A.
let R be the resistance of the filament lamp;
then R = `"V"/"I" = 3/0.5` = 6Ω
APPEARS IN
संबंधित प्रश्न
You have three resistors of values 2Ω, 3Ω and 5Ω. How will you join them so that the total resistance is more than 7Ω?
1) Draw a diagram for the arrangement
2) Calculate the equivalent resistance.
A p.d. of 10 V is needed to make a current of 0.02 A flow through a wire. Wire p.d. is needed to make a current of 250 mA flow through the same wire?
For the circuit shown in the diagram below:
What is the value of:
(i) current through 6 Ω resistor?
(ii) potential difference across 12 Ω resistor?
Which one of the following is the correct set-up for studying the dependence of the current on the potential difference across a resistor and why?
Point out two differences between e.m.f. and potential difference as applied to electric circuits.
In the figure given below, A, B and C are three ammeters. The ammeter B reads 0.5A. (All the ammeters have negligible resistance.)
Calculate:
(i) the readings in the ammeters A and C.
(ii) the total resistance of the circuit.
A cell of e.m.f 2.0 V and internal resistance 1Ω is connected to the resistors of 3Ω and 6Ω in series. Calculate:
(i) the current drawn from the cell,
(ii) the p.d. across each resistor,
(iii) the terminal voltage of the cell and
(iv) the voltage drop.
A 10 m long wire of a particular material is of resistance 5Ω What will be the resistance if the wire is stretched to double its length?
Conceptual question.
A bird sitting on a high power electric line is still safe. How?
Find out the following in the electric circuit given in Figure
- Effective resistance of two 8 Ω resistors in the combination
- Current flowing through 4 Ω resistor
- Potential difference across 4 Ω resistance
- Power dissipated in 4 Ω resistor
- Difference in ammeter readings, if any.
