To 10 Hz. Superimposed on this signal is 60-Hz noise with an amplitude of 0.1 V. It is desired to attenuate the 60-Hz signal to less than 10% of its value using a Butterworth filter. Select a filter order to perform this task if the corner frequency is 10 Hz.

If we square both sides we got:

We divide both sides by and we got:

Now we can apply log on both sides and we got:

And solving for n we got:

And replacing we got:

And since n needs to be an integer the correct answer would be n=2 for the filter order.

Explanation:

For this case we can use the formula for the Butterworth filter gain given by:

[tec] G = \frac{1}{\sqrt{1 +(\frac{f}{f_c})^{2n}}}[/tex]

Where:

G represent the transfer function and we want that G =0.1 since the desired signal is less than 10% of it's value

represent the corner frequency

represent the original frequency

n represent the filter order and that's the variable that we need to find

If we square both sides we got:

We divide both sides by and we got:

Now we can apply log on both sides and we got:

And solving for n we got:

And replacing we got:

And since n needs to be an integer the correct answer would be n=2 for the filter order.

as a general rule, scissors have blades less than 6 in (15 cm) long and usually have handles with finger holes of the same size. shears have blades scissors used to cut hair or fabric must be much sharper

the answer would be c. motion and direction

i hope this : )