Physics Lab (For Charandry only)dont bid

RL Circuit

Purpose:

The purpose of this experiment is to collect electric potential and current data within a

DC circuit that has in inductor and a resistor in series with each other. This will then allow for the

effect of data collection rate on the potential vs. time graphs to be determined.

Procedure:

• A series circuit with a power supply is constructed with a long bulb, a 5nH inductor and a

single-pole double throw switch.

• Make sure the power supply is in circuit with the bulb and inductor and close the switch.

Observe the behavior of the light bulb. Observe the light bulb again when the switch is

moved to the other position.

• Turn the power supply off and take the inductor out of the circuit. Observe the behavior

of the power supply and the bulb when the switch is moved to the other position.

• Put the 5mH inductor back in the circuit and replace the long bulb with the 10 ohm

resistor. Connect the leads of the voltage probe to each end of the inductor (red lead on

the nearest end to the resistor).

• Change data setup so the collection rate is 200 Hz and the duration is 5 seconds.

• Connect the current probe to the circuit, allowing it to be in series with the inductor and

the resistor.

• Zero the voltage probe and current probe. Start the data collection then close the switch.

When the data collection stops, reopen the switch and store the run.

• Increase the data-collection rate to 2000 Hz and reduce the duration to 1 second.

• Start the data collection and immediately close the switch. Once the data collection is

complete, reopen the switch. Store this run once a spike in potential is observed.

• Reduce the duration to .10s and enable triggering (set triggering value to 1.0V on

increasing trigger). Set the data collection to collect half of the samples before the

trigger and the other half after.

• Start the data collection and close the switch. Store this run once data is obtained.

• Collect another run, however increase the rate to 5000 Hz. Repeat the sets above and

store the run

Data:

L = 5 mH ; R = 10 Ω

Analysis:

1)

2)

3) Second run sampling rate = 2000 Hz

We were unsuccessful when attempting to perform a natural exponential curve at a sampling

rate of 2000 Hz for the second run.

4) Third run sampling rate = 2000 Hz with triggering

C Parameter: 2430 +/- 43.79

5) Final run sampling rate = 5000 Hz

A faster sampling rate is a higher frequency capable of collecting more samples per second of

the circuit data, thus creating a finer, higher quality graph.

The C parameter from this run has a lower margin of error than the C parameter from the third

run, it is roughly half the amount.

Third Run C Parameter: 2430 +/- 43.79

Final Run C Parameter: 2875 +/- 23.13

6) The C parameter is equivalent to the inverse of the time constant, 𝜏

𝜏 = LR

C = 1𝜏 = 1LR = RL =10 Ω5 10-3H = 2000 Hz

The theoretical C parameter is 2000 Hz

7)

Conclusion: