DC Electrical;

LO

Learning outcome (LO) Assessment Criteria In this assessment you will have the opportunity to present evidence that shows you are able to: Task no.

Evidence

(Page no)

LO 3

Be able to apply DC theory to solve electrical and electronic engineering problems. 3.1

Solve problems using Kirchoff’s laws to calculate currents and voltages in circuits.

3.2 Solve problems using circuit theorems to calculate currents and voltages in circuits.

3.3 Solve problems involving current growth/decay in L-R circuits and voltage growth/decay in C-R circuits.

Learner declaration

I certify that the work submitted for this assignment is my own and research sources are fully acknowledged.

Student signature: Date:

In addition to the above PASS criteria, this assignment gives you the opportunity to submit evidence in order to achieve the following MERIT and DISTINCTION grades

Grade Descriptor

Indicative characteristic/s

Contextualisation

D1

Use critical reflection to evaluate own work and justify valid conclusions Conclusions have been arrived at through synthesis of ideas and have been justified.

Conclusions have been made by processes and ideas and justifications regarding the series R-L and R-C variables and circuit behaviour. (Tasks 3 & 4)

D2

Take responsibility for managing and organising activities Activities have been effectively managed.

Autonomy / independence has been demonstrated All tasks have been accurately and concisely completed within the given time constraints. (All Tasks)

Please note that for unit assignments assessors should use these or other exemplar indicative characteristics for the individual grade descriptors from Annexe C of the HN specification or any other relevant indicative characteristics for the particular assignment. The indicative characteristic should then be contextualised. Only one indicative characteristic per grade descriptor, M2, M2, M3, D1, D2, D3 is required.

Assignment brief

Unit number and title 21881C Engineering Science

Qualification Pearson BTEC Level 4/5 HN Engineering Streams

Start date

Deadline/hand-in 25/5/15

Assessor Dr Warren Kent PhD CMath MIMA CSci MIET AKC PGCE QTS

Assignment title DC Electrical

Purpose of this assignment

To develop the students knowledge and application of DC Theory, Theorems and Laws and their application in electrical circuits.

Scenario

This Assignment has been designed to allow students to show evidence of the application of DC Theorems in realistic electrical circuits and supporting the learning outcome.

Task 1 : (LO3:3.1) D2

50 V

In the DC circuit shown above, apply Kirchoff’s laws to find the current in each branch.

Task 2 (LO3: 3.2) D2

2.

In the DC circuit shown above, apply Thevenin’s Theorem to find the current in the 25 ? resistor.

Task 3 (LO3: 3.3) D1 D2

For the series RC circuit shown above, where there is no initial charge

across the capacitor, on closing the switch, ‘S’, determine:

(a)

the initial value of the current,

(b)

the time constant of the circuit,

(c)

the current’s value after 1 second from switching on,

(d)

the voltage across the capacitor after 1.3 seconds from switch on,

(e)

the time from switch on when the resistor voltage was 32 V.

Task 4 (LO3: 3.3) D1 D2

From the series RL circuit shown above, where there is no initial

voltage across the inductor, on closing the switch, determine:

(a)

the steady-state value of the current flowing in the circuit,

(b)

the time constant of the circuit,

(c)

the induced voltage after 0.08 seconds,

(d)

the time taken for the current to rise to 75% of its final value,

(e)

the value of the current after 0.25 seconds.

Evidence checklist Summary of evidence required by student Evidence presented

Task 1 Circuit diagram showing the application of Kirchoff’s laws for the circuit’s variables.

Task 2 Circuit diagram showing the application of Thevenin’s Theorem for the circuits variables.

Task 3 Circuit diagram of the R-C circuit and tha application of DC theory for the solution of the circuit’s parameters.

Task 4 Circuit diagram of the R-L circuit and tha application of DC theory for the solution of the circuit’s parameters.

Sources of information:

Achievement Summary

Qualification Pearson BTEC Level 4/5 HN Engineering Steams

Assessor name

Dr W Kent PhD CMath CSci AKC PGCE QTS

Unit Number and title 21881C Engineering Science

Student name

Criteria Reference To achieve the criteria the evidence must show that the student is able to: Achieved?

(tick)

LO1

3.1 Solve problems using Kirchoff’s laws to calculate currents and voltages in circuits.

3.2 Solve problems using circuit theorems to calculate currents and voltages in circuits.

3.3

Solve problems involving current growth/decay in an L-R circuit and voltage growth/decay in a C-R circuit.

Higher Grade achievements (where applicable)

Grade descriptor

Achieved?

(tick)

Grade descriptor

Achieved?

(tick)

D1: Use critical reflection to evaluate own work and justify valid conclusions

D2: Take responsibility for managing and organising activities

Assignment Feedback

Formative Feedback: Assessor to Student

Through out this section of the module delivery.

Action Plan

Summative feedback

Feedback: Student to Assessor