n identical light bulbs, drawing P power from a voltage supply, are joined in series. The total power drawn is

Electric power can be defined as the rate at which work is done or energy is converted into an electrical circuit. It is basically a measurement of energy used in a span of time.

Step 1: Use of Formula

In order to calculate, we need to use the formula of electric power, which is given by:

P = VI

Here,

  • P = Power
  • V = Potential difference in Circuit
  • I = Electric Current

Power can be represented as:

⇒ P = I2R
⇒ \(P = {{V^2} \over R}\)

The two expressions were obtained by using Ohm’s Law, wherein Voltage, Current, and Resistance are all interrelated with one another. Ohm’s Law is given by:

V = IR

Where,

  • R = Resistance in the Circuit
  • V = Potential difference
  • I = Electric Current

Step 2: Find Solution

Let’s first consider the following readings:

  • A voltage of the source = V
  • Resistance of each bulb = R

Hence, \(R = {{V^2} \over P}\)

The amount of Power drawn by each bulb can be given by = i2R = \({{V^2} \over n^2R^2} \times R\)

=\({{V^2} \over n^2R} \)

= \({{P} \over n^2}\)

Read Also: Ohm’s Law and its Limitations


Related Questions:

  1. State Ohms law. How can it be verified experimentally?
  2. How do you find the resistance to Ohm's law?
  3. What is the necessary condition for a conductor to obey Ohm's Law?
  4. What is Effective Resistance?
  5. Why is the curve representing Ohm's law linear?
  6. Why Do We Use Ohm's Law?
  7. How many 176 ohm resistors (in parallel) are required to carry 5 A on a 220 V line?
  8. What are the 3 forms of Ohm's law
  9. What Is Ohm's Law Graph?
  10. What are the limitations of Ohm's Law?
  11. What are the applications of ohm's law used in daily life?
  12. State Ohms Law. Express It Mathematically. Define Si Unit Of Resistance.
  13. Is resistance constant in Ohm's law?
  14. Draw a circuit diagram to verify ohm’s law.

Check Out:

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                        CBSE CLASS XII Previous Year Papers

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