Advertisements
Advertisements
प्रश्न
A current of 100 mA. flows through a wire. The charge on an electron is 1.6 × 10-19 C. Find the number of electrons passing per second through the cross-section of the conductor.
Advertisements
उत्तर
Given: I = 100mA = 100 × 10-3 A = 0.1A, e = 1.6 × 10-19 C
Let n electrons are passing per second. Charge on one electron = e
Total charge passed in one second = ne
Thus, i = ne or
n = `"i"/"e" = 0.1/(1.6 xx 10^-19) = 6.25 xx 10^17`.
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.
The potential difference between the terminals of an electric iron is 240 V and the current is 5.0 A. What is the resistance of the electric iron?
If the potential difference between the ends of a fixed resistor is halved, the electric power will become:
A current of 1.6 mA flows through a conductor. If charge on an electron is –1.6 × 10-19 coulomb, find the number of electrons that will pass each second through the cross section of that conductor.
Three electric cells of potential difference 1.5 V each have been connected as a battery. The potential differences of the battery will be ____________ V.
Define the following:
Potential difference
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.
Exercise.
Calculate the amount of charge that would flow in 2 hours through an element of an electric bulb drawing a current of 2.5 A.
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.
