Experiment 4 Pre-lab

What is the purpose of procedure A?

To measure the current of each circuit.

What is the purpose of Procedure B ?

To measure the lightbulbs resistance.

Define the equivalent resistance for a parallel circuit: (Select all that apply)

1/Req= R1+R2/R1R2 1/Req= 1/R1 + 1/R2

In procedure A, what voltage value do you set the power supply to?

15 V

Calculate the equivalent resistance of circuit diagram 2. How much current would be drawn from a 12 V battery connected to this circuit? If you are unable to see the image, please reference Circuit Diagram 2: Parallel in your lab manual.

58 mA

Calculate the equivalent resistance for the following circuit. If you are unable to see the image, please reference Circuit Diagram 1: Series in your lab manual.

890 Ohms

What is a resistor?

A resistor is an ohmic device. A resistor generally means a device that obeys Ohm's Law and has a resistance R.

Define equivalent resistor:

An equivalent resistor is a single resistor that could replace a more complex circuit and produce the same total current for the same total voltage.

The resistance in this experiment will be determined both theoretically and experimentally. How will the experimental resistance be calculated?

By measuring the voltage and current.

True or False: The resistance of the lightbulbs is constant.

False

True or False: We will use an ammeter to measure the current provided by the power supply.

False

Explain the difference between the series and parallel circuits in terms of calculating equivalent resistance.

In parallel, the resistance adds as reciprocals. In series, the resistances are additive.

What will be used to determine the measured resistance values?

Oscilloscope Digital Multimeter Function Generator

What materials will be utilized for this experiment?

Oscilloscope, digital multimeter, and DC power supply.

It is useful to consider power in terms of current and resistance. What is an alternative way form for power?

P= I * I * R

Define power.

P=IV

What method will be used to compare the theoretical and experimental values recorded?

Percent Difference

What is power?

Power is the rate at which work is done for a system.

Define the equivalent resistance for a series circuit:

Req=R1+R2

Two or more resistors can be connected in , or in .

Series, Parallel

Why can't we use an ammeter to measure the current provided by the power supply?

The lightbulbs current being drawn is much larger than with the resistors

What is the purpose of this experiment?

The purpose of this experiment is to understand series and parallel circuits, how to calculate their equivalent resistance, and how to construct the laboratory.

True or False: You will examine the lightbulbs in both series and parallel circuits.

True

Define Ohm's Law

V=IR

Identify the units of power.

Watts