this is a university physic 2 lab i think it is simple. please read the both attachment.
Building the Circuit
1. Open the circuit simulator by going to the following website: http://falstad.com/circuit/.
A sample circuit is running when the page opens.
2. Click the Circuits pulldown menu then hover over the Basics submenu. Click Capacitor.
This will automatically load our basic RC circuit.
3. Right click on the resistor and choose Edit. This will allow you to set the resistance. For
now, set the resistance to 10 kΩ by typing ‘10k’ into the textbox.
4. Right click on the capacitor and choose Edit. Set the capacitance to 330 F. The ‘u’
notation in the textbox indicates ‘micro’.
5. Right click on the Battery and choose Edit. Set the Voltage to 4.5 V.
6. The graph at the bottom of the screen is the “Scope” and displays the voltage across the
capacitor in green and the current in the circuit in yellow. You will notice that to the right
of the graph is a time value and that time is passing but very slowly. You can alter the
flow of time here by adjusting the red and grey slider in the upper right of the screen
labelled Simulation Speed. You can also pause the flow of time entirely by clicking the
Run/Stop button.
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Data Collection
1. Charge the capacitor by closing the switch to the left such that the Capacitor charges
through the Resistor. Let the capacitor charge until the voltage across it is at least 4
volts. You can adjust the simulation speed.
2. Move the switch to the right position so that the Capacitor discharges through the
Resistor. If you sped up the simulation speed, you may want to slow it back down and
be ready to push the Run/Stop button.
3. When the voltage across the capacitor reaches 3 volts, record the value for t found to
the right of the Scope Display in Table 1.
4. When the voltage reaches 1.5 volts, stop the watch and record the value for t in Table
1. Calculate and record the measured time of the half-life, h in Table 1 as h = tf – ti.
5. Calculate and record the measured time constantC of the RC circuit in Table 1 as C =
h / ln(2).
6. Calculate and record both the theoretical time constant and theoretical half-life of the
circuit using C = RC and h = C ln(2). Record these values in Table 1.
7. Calculate and record the percent error in your experimental value of the time constant
and half-life for this combination of capacitor and resistor. Given that this is a
simulation, the percent error should be extremely low. Record these in Table 1.
8. Right click on the Resistor and choose Edit. Set the resistance to 22 kΩ and repeat
steps 1 – 7. Record all results in Table 2.
9. Right click on the Resistor and choose Edit. Set the resistance to 10 kΩ. Right click
on the Capacitor and choose Edit. Set the capacitance to 1000 µF. Repeat steps 1-7
and record all results in Table 3.
10. Right click on the Capacitor and choose Edit. Set the capacitance to 2200 µF and
repeat steps 1 – 7. Record all results in Table 4.
11. Right click on the Resistor and choose Edit. Set the resistance to 22 kΩ and repeat
steps 1 – 7. Record all results in Tab