Math Problem Statement

Find V and I in each of these circuits and determine the power dissipated in each resistor, using Ohm's Law.

Solution

Let's solve this step by step for each circuit using Ohm's Law and the power formula.


(i) Circuit:

  1. Ohm’s Law: V=IRV = IR, where:

    • V=10VV = 10 \, \text{V} (voltage of the battery),
    • R=50ΩR = 50 \, \Omega (resistance of the resistor).

    Solve for II: I=VR=1050=0.2A.I = \frac{V}{R} = \frac{10}{50} = 0.2 \, \text{A}.

    Thus, the current I=0.2AI = 0.2 \, \text{A}.

  2. Power Dissipated: Power (PP) is given by: P=VI=100.2=2W.P = V \cdot I = 10 \cdot 0.2 = 2 \, \text{W}.

    Alternatively, using P=I2RP = I^2 R: P=(0.2)250=0.0450=2W.P = (0.2)^2 \cdot 50 = 0.04 \cdot 50 = 2 \, \text{W}.


(ii) Circuit:

  1. Ohm’s Law: Here, the current I=2AI = 2 \, \text{A}, and the resistance R=50ΩR = 50 \, \Omega.

    Solve for VV: V=IR=250=100V.V = IR = 2 \cdot 50 = 100 \, \text{V}.

    Thus, the voltage V=100VV = 100 \, \text{V}.

  2. Power Dissipated: Power (PP) is given by: P=VI=1002=200W.P = V \cdot I = 100 \cdot 2 = 200 \, \text{W}.

    Alternatively, using P=I2RP = I^2 R: P=(2)250=450=200W.P = (2)^2 \cdot 50 = 4 \cdot 50 = 200 \, \text{W}.


Final Results:

  1. Circuit (i):

    • I=0.2AI = 0.2 \, \text{A},
    • P=2WP = 2 \, \text{W}.
  2. Circuit (ii):

    • V=100VV = 100 \, \text{V},
    • P=200WP = 200 \, \text{W}.

Would you like more explanation or have further questions?


5 Questions to Explore Further:

  1. How does Ohm's Law change in parallel circuits?
  2. What happens to the current if the resistance is doubled in circuit (i)?
  3. How is power dissipation related to energy transfer?
  4. Can you calculate the total energy consumed in 1 hour for circuit (ii)?
  5. What would happen if the resistor in circuit (ii) were replaced with a 25 Ω\Omega resistor?

Tip:

Always double-check units for consistency when solving electrical circuit problems!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Ohm's Law
Power dissipation in electrical circuits

Formulas

Ohm's Law: V = IR
Power: P = VI
Power (alternative): P = I^2R

Theorems

Ohm's Law

Suitable Grade Level

Grades 9-12