*Question E5B03:
How is impedance in polar form converted to an equivalent admittance?*  

*Correct Answer is  B: Take the reciprocal of the magnitude and change the sign of the angle*  

### AI Response: (may contain errors)  

To convert impedance in polar form to an equivalent admittance, we use the following relationship:

$$Y = \frac{1}{Z}$$

where:
- $Y$ = admittance
- $Z$ = impedance

In polar form, impedance is expressed as $Z = |Z| \angle \theta$, where $|Z|$ is the magnitude and $\theta$ is the phase angle. The conversion to admittance involves taking the reciprocal of the magnitude and changing the sign of the angle.

### Correct Answer Explanation:
- **Correct Answer: B**: Take the reciprocal of the magnitude and change the sign of the angle.
  
  When you take the reciprocal of the impedance $Z = |Z| \angle \theta$, the admittance $Y$ becomes:
  
  $$Y = \frac{1}{|Z|} \angle (-\theta)$$
  
  This means:
  - The magnitude of $Y$ is $\frac{1}{|Z|}$.
  - The angle of $Y$ is $-\theta$ (the sign of the angle is changed).

### Incorrect Choices Explanation:
- **Choice A**: Take the reciprocal of the angle and change the sign of the magnitude.
  - This is incorrect because you do not take the reciprocal of the angle; you take the reciprocal of the magnitude.

- **Choice C**: Take the square root of the magnitude and add 180 degrees to the angle.
  - This is incorrect because the conversion does not involve taking the square root, and adding 180 degrees is not part of the reciprocal process.

- **Choice D**: Square the magnitude and subtract 90 degrees from the angle.
  - This is incorrect because squaring the magnitude and subtracting 90 degrees does not relate to the conversion of impedance to admittance.

### Summary:
To convert impedance in polar form to admittance:
- Take the reciprocal of the magnitude.
- Change the sign of the angle.

This method ensures you correctly find the admittance corresponding to the given impedance.