- #1
Taniaz
- 364
- 1
Homework Statement
In this experiment, we're trying to study the characteristics of a light bulb. Here are the steps outlined for us:
1. Use a potentiometer to vary the voltage across the bulb measured by the voltmeter V. Collect data of V-values and corresponding I'-values from the ammeter over the voltage range 0-12 V.
2. Remove the bulb from the circuit and repeat (1) using identical voltage values. The new current values i represent the current drawn by the voltmeter itself during part (1). Tabulate I' and i with corresponding V, then calculate the corrected values I = I' - i, tabulating these also.
Homework Equations
R= v/I and P=VI
The Attempt at a Solution
We are able to set the experiment for part (1) and we get the values required. For the second part, the only problem is, we are using a rheostat as a potentiometer so we've connected all three terminals of the rheostat. The bottom two terminals of the rheostat have been connected to the D.C power supply and then another connection was made to the voltmeter from the wiper to one of the bottom ends as well and we got ourselves a potential divider.
Now the only concern is where do we place the ammeter to be able to measure the current? We've tried different positions but most of the time, either the ammeter would work alone or the voltmeter, never together!