Advertisements
Advertisements
प्रश्न
Explain why potential difference is always less than the e.m.f. of a cell?
Advertisements
उत्तर
When a cell is in closed circuit, i.e., when current is drawn from it, then the potential difference between its electrodes is called the terminal voltage. It is always less than the e.m.f. because when charge flows in a circuit, some energy is spent in the flow of charge through the electrolyte of the cell.
संबंधित प्रश्न
What is meant by saying that the potential difference between two points is 1 V?
The values of current I flowing in a given resistor for the corresponding values of potential difference V across the resistor are given below:
| I (amperes) | 0.5 | 1.0 | 2.0 | 3.0 | 4.0 |
| V (volts) | 1.6 | 3.4 | 6.7 | 10.2 | 13.2 |
Plot a graph between V and I and calculate the resistance of that resistor.
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.
Calculate the work done in moving a charge of 4 coulombs from a point at 220 volts to another point at 230 volts.
What do you understand by the term "potential difference"?
The other name of potential difference is:
b. The values of potential difference V applied across a resistor and the correponding values of current I flowing in the resistor are given below:
| Potential difference, V (in volts) | : | 2.5 | 5.0 | 10.0 | 15.0 | 20.0 | 25.0 |
| Current, I (in amperes) | : | 0.1 | 0.2 | 0.4 | 0.6 | 0.8 | 1.0 |
Plot a graph between V and I, and calculate the resistance of the resistor.
c. Name the law which is illustrated by the above V-I graph.
What current will be taken by a 920 W appliance if the supply voltage is 230 V?
The following table shows current in Amperes and potential difference in Volts.
Which law will the graph prove? Explain the law.
A negative charge will move from ______ to ______ potential.
