ENGIN1002-Measuring Current and Voltage - Engineering Assignment Help

Assignment Task

Task 

Aim

•  To discover whether the current is used up in a circuit; the effect of increased resistance on the flow of current and what happens to the flow of current at a junction.
•  To learn how to measure voltage, current and resistance using online simulator.

Brief Introduction
Conventional electric current is defined as the rate of transfer of positive electric charge with respect to time through a conductor. In electronic circuits, electrons are usually the charge carriers, so the actual flow of these negative charge carriers are in the opposite direction to the conventional current flow.
Electric charges move quite freely through conductors but not through insulators.
A DC (Direct Current) power supply, such as a battery, has two terminals, positive and negative. Electric current flows from the positive (higher potential) to the negative (lower potential). The actual electrons move in the opposite direction to the electric current.

Prediction 1.01-                                                                                                                                                                                                                                              Which model do you think best describes how current will flow through the bulb? Why?

Prediction 1.02
For the circuit in Figure 1.5 (a), what can you predict about the current entering the lamp and the current leaving the lamp?

Prediction 1.03
Predict the order of the relative currents (highest to lowest) going through each of the three bulbs (P, Q and R) in Figures 1.5 (a) and 1.5 (b).

Prediction 1.04
Predict what do you think happens to the total resistance of the circuit as more bulbs are added in series in Figure 1.5 (b).

Prediction 1.05
Does the addition of bulb R affect the current through bulb Q? Does less current flow through bulb R compared to bulb Q? Predict and briefly discuss your answers.

Prediction 1.06
Describe the relationship between the total resistance of a circuit and the current flowing through it

Prediction 1.07
Is the current that leaves the positive terminal of the battery greater than, less than or equal to the current that returns to the negative terminal of the battery?

Prediction 1.08
When current flows through the bulb circuits, the bulb(s) give off light and heat: what is being used up as the current flows through a bulb?

Prediction 1.09
As the total resistance of a circuit decreases, what happens to the current flowing from the power supply [increases, decreases, remains unchanged]? Explain briefly.

Prediction 1.10
Predict the order of the relative magnitude of the currents (highest to lowest) going through each bulb (i.e. P, Q, R, S, T) in Figures 1.5 (a), 1.5 (b) and 1.5 (c)

Prediction 1.11
What happens to the total current from the DC power supply as more parallel branches are added, each with
one identical bulb? Explain and justify.

Prediction 1.12
From all your predictions so far, can you determine the relationship between the brightness of a bulb and the current passing through it?

Section 2: Working with Resistors
Section 1 provided an opportunity to make qualitative observations of current flowing through light bulbs. It is difficult to make quantitative measurements with light bulbs as the resistance of a light bulb is not constant but varies depending upon the current flowing through it and hence the change in temperature of the filament.
Resistors are electronic devices which have constant resistance regardless of the current flowing through them. A resistance can be measured directly using an ohmmeter or can be determined indirectly from the definition of resistance: R = V/I.
In this section, you will be working with resistors and you will get to know how they can be measured indirectly. Resistors are colour coded to give you a good estimate of their value, but often it is easier and more accurate to measure the resistance value using the direct or indirect method.

Observation 2.01
? Using Multisim Live, construct the circuit shown in Figure 2.1 using the 5 V DC power supply across the two resistors in series, R1 = 1.0 k? and R2 = 4.7 k?. Note that in Multisim Live there is no multimeter as such. You have to use a current and voltage probe at appropriate location where you need to measure. Furthermore, in the simulator, you always have to ground your circuit. Refer to Lab 2 sheet for help to use voltage and current probes.
? From the measurement probes, note the current through the circuit (I) and the voltage (V2) across R2. From the values of current and voltage, calculate R2.

Explanation 2.01
Does the calculated value of R2 match with the actual value of R2? Explain your answer.

Prediction 2.02
Using the concept of the light bulbs in Section 1, predict the relationship (> < =) between the magnitude of the
currents you would expect to flow through the 1 k? resistors (P, Q, R, S and T in Figure 2.2 (a), (b) and (c)).

Observation 2.02
? Using “I = V/R”, calculate the current (in mA) that will flow through the 1 k? resistors (P, Q, R, S and T in
Figure 2.2 (a), (b) and (c)).

? Using Multisim Live, construct the circuits shown in Figure 2.2 (a), (b) and (c) with the DC supply set at 5.0 V. Measure the current flowing through each of the five resistors (P, Q, R, S and T) with the ammeter probe. Using a voltmeter probe, also measure the voltage across each of the five resistors (P, Q, R, S and T). Note that in Multisim Live there is no multimeter as such. You have to use a current and voltage probe at appropriate location where you need to measure. Furthermore, in the simulator, you always have to ground your circuit. Refer to Lab 2 sheet for help to use voltage and current probes. Calculate the value of each of the five resistors (P, Q, R, S and T).

Explanation 2.02
Does your predicted relationship between the magnitude of current through each of the five resistors (P, Q, R, S and T) match with the measured ones? If not, can you explain what assumption(s) you were making that now seem false? Also, does your calculated values of resistance matches with the actual ones? Discuss.

Section 3: An analogy to electrical current flow
It is possible to use a two-dimensional mechanical analog to model current flow through conductors, where the balls represent the charges and the pegs represent the atoms in the conductor.

What happens to the gravitational potential energy given to the bowling balls by the ramp height?

How is this energy loss exhibited in the circuit you wired that consists of a power supply, two wires, and a bulb?

Is there any difference in the number of bowling balls starting at the top of the ramp and reaching the bottom?

Does the current in the circuit in Figures1.5 (a) and (b) change around the loop? Why or why not?

What do you think the height of the ramp represents in an electrical circuit?

Section 4: An analogy to series and parallel connections
Consider the ramp analogy again from Figure 3.1.
Connecting the two bulbs in series is like doubling the number of pegs on the path of the rolling balls. Will that increase the number of collisions? Will that slow down the average speed of the balls and therefore the number of balls reaching the bottom per second? Relate this to your observation about current flow.

Connecting two bulbs in parallel is like putting two ramps side by side. What can you say about total number of balls going to come down per second from both? Is there any change in the number of collisions with the pegs on each ramp? Relate this to your observation about current flow.

This ENGIN1002-Engineering Assignment has been solved by our Engineering Expert at My Uni Paper. Our Assignment Writing Experts are efficient to provide a fresh solution to this question. We are serving more than 10000+ Students in Australia, UK & US by helping them to score HD in their academics. Our Experts are well trained to follow all marking rubrics & referencing Style. Be it a used or new solution, the quality of the work submitted by our assignment experts remains unhampered. 

You may continue to expect the same or even better quality with the used and new assignment solution files respectively. There’s one thing to be noticed that you could choose one between the two and acquire an HD either way. You could choose a new assignment solution file to get yourself an exclusive, plagiarism (with free Turn tin file), expert quality assignment or order an old solution file that was considered worthy of the highest distinction.