The Q of a tuned amplifier is 50. If the resonant frequency for the amplifier is 1000kHZ, then bandwidth is ___________

The correct answer is $\boxed{\text{D}}$.

The bandwidth of a tuned amplifier is given by the formula:

$$BW = \frac{f_0}{Q}$$

where $f_0$ is the resonant frequency and $Q$ is the quality factor.

In this case, $f_0 = 1000$ kHz and $Q = 50$. Substituting these values into the formula, we get:

$$BW = \frac{1000 \text{ kHz}}{50} = 20 \text{ kHz}$$

Therefore, the bandwidth of the tuned amplifier is 20 kHz.

Option A is incorrect because it is the resonant frequency, not the bandwidth.

Option B is incorrect because it is twice the bandwidth.

Option C is incorrect because it is half the bandwidth.