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The voltage over a cycle varies as V=V...

The voltage over a cycle varies as
`V=V_(0)sin omega t` for `0 le t le (pi)/(omega)`
`=-V_(0)sin omega t` for `(pi)/(omega)le t le (2pi)/(omega)`
The average value of the voltage one cycle is

A

`(V_(0))/(sqrt(2))`

B

`(V_(0))/(2)`

C

zero

D

`(2V_(0))/(pi)`

Text Solution

AI Generated Solution

The correct Answer is:
To find the average value of the voltage over one complete cycle, we can follow these steps: ### Step 1: Understand the Voltage Function The voltage \( V(t) \) is defined piecewise over one complete cycle: - For \( 0 \leq t \leq \frac{\pi}{\omega} \): \[ V(t) = V_0 \sin(\omega t) \] - For \( \frac{\pi}{\omega} < t \leq \frac{2\pi}{\omega} \): \[ V(t) = -V_0 \sin(\omega t) \] ### Step 2: Set Up the Average Voltage Formula The average value of the voltage over one cycle is given by: \[ V_{avg} = \frac{1}{T} \int_0^T V(t) \, dt \] where \( T = \frac{2\pi}{\omega} \). ### Step 3: Calculate the Integral We will split the integral into two parts: 1. From \( 0 \) to \( \frac{\pi}{\omega} \) 2. From \( \frac{\pi}{\omega} \) to \( \frac{2\pi}{\omega} \) Thus, we have: \[ V_{avg} = \frac{1}{T} \left( \int_0^{\frac{\pi}{\omega}} V_0 \sin(\omega t) \, dt + \int_{\frac{\pi}{\omega}}^{\frac{2\pi}{\omega}} -V_0 \sin(\omega t) \, dt \right) \] ### Step 4: Evaluate the First Integral For the first integral: \[ \int_0^{\frac{\pi}{\omega}} V_0 \sin(\omega t) \, dt = V_0 \left[-\frac{1}{\omega} \cos(\omega t)\right]_0^{\frac{\pi}{\omega}} = V_0 \left[-\frac{1}{\omega} \cos\left(\pi\right) + \frac{1}{\omega} \cos(0)\right] \] \[ = V_0 \left[-\frac{1}{\omega} (-1) + \frac{1}{\omega} (1)\right] = V_0 \left[\frac{2}{\omega}\right] \] ### Step 5: Evaluate the Second Integral For the second integral: \[ \int_{\frac{\pi}{\omega}}^{\frac{2\pi}{\omega}} -V_0 \sin(\omega t) \, dt = -V_0 \left[-\frac{1}{\omega} \cos(\omega t)\right]_{\frac{\pi}{\omega}}^{\frac{2\pi}{\omega}} = -V_0 \left[-\frac{1}{\omega} \cos\left(2\pi\right) + \frac{1}{\omega} \cos\left(\pi\right)\right] \] \[ = -V_0 \left[-\frac{1}{\omega} (1) + \frac{1}{\omega} (-1)\right] = -V_0 \left[-\frac{2}{\omega}\right] = \frac{2V_0}{\omega} \] ### Step 6: Combine the Integrals Now, we can combine both integrals: \[ \int_0^{\frac{2\pi}{\omega}} V(t) \, dt = \frac{2V_0}{\omega} + \frac{2V_0}{\omega} = \frac{4V_0}{\omega} \] ### Step 7: Calculate the Average Voltage Now substitute back into the average voltage formula: \[ V_{avg} = \frac{1}{\frac{2\pi}{\omega}} \cdot \frac{4V_0}{\omega} = \frac{4V_0}{2\pi} = \frac{2V_0}{\pi} \] ### Final Result The average value of the voltage over one cycle is: \[ \boxed{\frac{2V_0}{\pi}} \]

To find the average value of the voltage over one complete cycle, we can follow these steps: ### Step 1: Understand the Voltage Function The voltage \( V(t) \) is defined piecewise over one complete cycle: - For \( 0 \leq t \leq \frac{\pi}{\omega} \): \[ V(t) = V_0 \sin(\omega t) \] ...
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