*Question E5D09:
What happens to reactive power in ideal inductors and capacitors?*  

*Correct Answer is  B: Energy is stored in magnetic or electric fields, but power is not dissipated*  

### AI Response: (may contain errors)  

In an ideal inductor and capacitor, reactive power behaves differently than real power. Let's break down the correct answer and the other choices.

### Correct Answer: 
**B: Energy is stored in magnetic or electric fields, but power is not dissipated.**

- **Explanation**: 
  - In an ideal inductor, energy is stored in the magnetic field when current flows through it. 
  - In an ideal capacitor, energy is stored in the electric field when voltage is applied across its plates. 
  - Reactive power (measured in VARs) represents the energy that oscillates between the source and the reactive components (inductors and capacitors) but does not result in net energy loss in the circuit. Thus, it is not dissipated as heat.

### Why the Other Choices are Incorrect:

- **A: It is dissipated as heat in the circuit.**
  - **Explanation**: This statement is true for resistive components, where real power is converted to heat. However, in ideal inductors and capacitors, there is no energy loss as heat; they only store and release energy.

- **C: It is canceled by Coulomb forces in the capacitor and inductor.**
  - **Explanation**: While there are forces at play in capacitors and inductors, reactive power is not "canceled" by these forces. Instead, it oscillates back and forth between the source and the reactive components without being consumed.

- **D: It is dissipated in the formation of inductive and capacitive fields.**
  - **Explanation**: This is incorrect because the formation of these fields does not result in energy dissipation. In ideal components, energy is stored, not lost.

### Useful Concepts:
- **Reactive Power (Q)**: 
  - Reactive power is defined as the power that alternates between the source and the reactive components. It can be calculated using the formula:
  
  $$Q = V \times I \times \sin(\phi)$$
  
  where:
  - $V$ = voltage across the component
  - $I$ = current through the component
  - $\phi$ = phase angle between voltage and current

- **Energy Storage**:
  - For an inductor, the energy stored ($W_L$) is given by:
  
  $$W_L = \frac{1}{2} L I^2$$
  
  where $L$ is the inductance and $I$ is the current.
  
  - For a capacitor, the energy stored ($W_C$) is given by:
  
  $$W_C = \frac{1}{2} C V^2$$
  
  where $C$ is the capacitance and $V$ is the voltage.

Understanding these concepts will help clarify the behavior of reactive power in circuits involving inductors and capacitors.