Experiment 3

# Experiment 3 - Experiment 3 DC CIRCUITS Voltage Current...

This preview shows pages 1–4. Sign up to view the full content.

Experiment 3. DC CIRCUITS: Voltage, Current & Resistance PHY 134 (Section 11)

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
Purpose The experiment was done to learn the basic concepts of Direct Current (DC) electric circuits by measuring voltages and currents in some simple circuits. Apparatus Voltmeter, Wire-Coil Resistor, Slide, Double-pole Single-Throw Switch, Input (3 volts DC), Ammeter, Multimeter (Ohm Meter), Carbon resistor (2), Light bulb (2), red and black wires. Theory Direct circuit (DC) is the constant flow of electric charge. The unit of current (I) is Amp, which is c/s. Voltage (V) is ability to cause current and resistance R is measured in unit, ohm(Ω). Ohm’s law is V=IR. When V and I are plotted, the slope of the graph is R, resistance. In series connection, R eff = R 1 + R 2, where in parallel connection, (1/ R eff ) =(1/ R 1 ) +(1/ R 2 ). Procedure For the first experiment, a voltage source was connected using the diagram given. Then, the voltage change was observed whether it changes linearly or not. Then, using the voltage source connected, a resistor, and an ammeter, the Ohm’s law was examined. Voltage and the current were measured and using the data, resistance was calculated for eight different voltages. Then, V and I were plotted and R was obtained from the slope of the graph. The value of R was also measured using the Multimeter as an Ohm meter. And the color code was also used to figure out the theoretical R value. Then, the carbon resistor was replaced with one light bulb. The brightness of the bulb and the current was observed.
Series and parallel connections were examined. First, two bulbs were used in series. The brightness was observed, and one of the bulbs was removed from the socket to see what happens. Then, the two bulbs were connected in parallel. Again, the brightness of each bulb was observed

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

## This note was uploaded on 04/10/2008 for the course PHY 134 taught by Professor Chang during the Fall '07 term at UMass (Amherst).

### Page1 / 10

Experiment 3 - Experiment 3 DC CIRCUITS Voltage Current...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online