Lab Experiment #7:

Oscilloscope

David McNeary Partner: Glendy Lara PHYS 200BL 10/25/2021

Data

Scope setup

| Timebase (s/div) | T (div) | T (s) | Chan. 1 scale (V\div) | V_m (div) | V_m (V) | | — | — | — | — | — | — | | $1 \frac{\text{ms}}{\text{div}}$ | $0.6\text{ div}$ | $0.6 \times 10^-3\text{ s}$ | $1 \frac{\text{V}}{\text{div}}$ | $2\text{ div}$ | $2\text{ V}$ | | $0.5 \frac{\text{ms}}{\text{div}}$| $1.25\text{ div}$ | $0.625 \times 10^-3\text{ s}$ | $1 \frac{\text{V}}{\text{div}}$ | $2\text{ div}$ | $2\text{ V}$ | | $0.1 \frac{\text{ms}}{\text{div}}$ | $6.3\text{ div}$ | $0.63 \times 10^-3\text{ s}$ | $1 \frac{\text{V}}{\text{div}}$ | $2\text{ div}$ | $2\text{ V}$ | | $0.1 \frac{\text{ms}}{\text{div}}$ | $6.4\text{ div}$ | $0.64 \times 10^-3\text{ s}$ | $2 \frac{\text{V}}{\text{div}}$ | $1\text{ div}$ | $2\text{ V}$ | | $0.1 \frac{\text{ms}}{\text{div}}$ | $6.35\text{ div}$ | $0.635 \times 10^-3\text{ s}$ | $0.5 \frac{\text{V}}{\text{div}}$ | $4\text{ div}$ | $2\text{ V}$ | The values of the period T compared to the voltage V remain fairly constant: there is no significant quantitative change in voltage vs. time as the scale definitions are changed.

Circuit measurements

| Set frequency f_s | ΔT | T | V_{m, bc} (div) | V_{m, ac} (V) | | — | — | — | — | — | | $1000 \text{ Hz}$ | $0.25 \text{ div} \times 0.0002\frac{\text{s}}{\text{div}} = 5\times10^{-5}\text{ s}$ | $4.8 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 4.8\times10^{-4}\text{ s}$ | $0.8 \text{ div} \times 0.5\frac{\text{V}}{\text{div}} = 0.4\text{ V}$ | $2 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 2\text{ V}$ | | $2000 \text{ Hz}$ | $0.4 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 4\times10^{-5}\text{ s}$ | $2.4 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 2.4\times10^{-4}\text{ s}$ | $0.6 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 0.6\text{ V}$ | $2 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 2\text{ V}$ | | $3000 \text{ Hz}$ | $0.3 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 3\times10^{-5}\text{ s}$ | $2.1 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 2.1\times10^{-4}\text{ s}$ | $0.7 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 0.7\text{ V}$ | $2 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 2\text{ V}$ | | $4000 \text{ Hz}$ | $0.3 \text{ div} \times 50\frac{\mu\text{s}}{\text{div}} = 1.5\times10^{-5}\text{ s}$ | $1.4 \text{ div} \times 0.1\frac{\text{ms}}{\text{div}} = 1.4\times10^{-4}\text{ s}$ | $0.8 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 0.8\text{ V}$ | $2 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 2\text{ V}$ | | $5000 \text{ Hz}$ | $0.2 \text{ div} \times 50\frac{\mu\text{s}}{\text{div}} = 1\times10^{-5}\text{ s}$ | $2.3 \text{ div} \times 0.1\frac{\mu\text{s}}{\text{div}} = 1.15\times10^{-4}\text{ s}$ | $0.9 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 0.9\text{ V}$ | $2 \text{ div} \times 1\frac{\text{V}}{\text{div}} = 2\text{ V}$ |

Calculations

| Set frequency f_s | f_exp (Hz) | $\phi$₁ (rad) | $\phi$₂ (rad) | $\phi$_avg (rad) | tan $\phi$_avg | | — | — | — | — | — | — | | $1000 \text{ Hz}$ | $2100 \text{Hz}$ | $1.4\text{ rad}$ | $0.65\text{ rad}$ | $1.03\text{ rad}$ | $1.67$ | | $2000 \text{ Hz}$ | $4100 \text{Hz}$ | $1.3\text{ rad}$ | $1.1\text{ rad}$ | $1.2\text{ rad}$ | $2.57$ | | $3000 \text{ Hz}$ | $4800 \text{Hz}$ | $1.2\text{ rad}$ | $0.90\text{ rad}$ | $1.05\text{ rad}$ | $1.74$ | | $4000 \text{ Hz}$ | $7100 \text{Hz}$ | $1.2\text{ rad}$ | $0.67\text{ rad}$ | $0.94\text{ rad}$ | $1.37$ | | $5000 \text{ Hz}$ | $8700 \text{Hz}$ | $1.1\text{ rad}$ | $0.55\text{ rad}$ | $0.83\text{ rad}$ | $1.09$ | From slope: $RC = 1.33\times 10^{-5} \text{ seconds}$ From given values: $RC = 5.94\times 10^{-5} \text{ seconds}$

Data sheet + Quiz