Divider

Part I

The questions in this section refer to the following circuit:

For a given set of values for R_1 and R_2, if R_2 is then increased, will the voltage V_o increase or decrease?
-- increase decrease

If R_1 = 100\Omega and R_2 = 10K\Omega, approximately what is the ratio \frac{V_o}{V_s}? (Enter a floating point number)

\frac{V_o}{V_s} \approx~

If R_1 = 10K\Omega and R_2 = 100\Omega, approximately what is the ratio \frac{V_o}{V_s}? (Enter a floating point number)

\frac{V_o}{V_s} \approx~

If V_o = \frac{1}{17}V_s, what is the ratio \frac{R_1}{R_2}? (Enter a floating point number)

\frac{R_1}{R_2} =~

Part II

Note that the only difference between this circuit and the one in the previous part is the addition of R_3. We are interested in the effect on V_o of adding this resistor.

Call the voltage across R_2 when R_3 is not present V_d, and assume that R_1 = R_2 = 1K\Omega.

If R_3 has a very high value, say 100K\Omega, how does the new value of V_o compare to the value V_d (defined above)? Enter the approximate numerical value of \frac{V_o}{V_d}.

\frac{V_o}{V_d} \approx~

If R_3 has a very low value, say 10\Omega, how does the new value of V_o compare to the value V_d (defined above)? Enter the approximate numerical value of \frac{V_o}{V_d}.

\frac{V_o}{V_d} \approx~

If R_1 = R_2 = R_3, how does the new value of V_o compare to the value V_d (defined above)? Enter the numerical value of \frac{V_o}{V_d}.

\frac{V_o}{V_d} =~