quit

proceedTo begin,

please click here

To begin, please click here

quitIntroductionIntroduction

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

back

Objectives:

- Students should be able to explain the relationship between power and energy - Students should be able to identify the usage of electricity for various household appliances - Students should be able to calculate energy cost Target Group:

Secondary 3 students

Duration/Mode:

2 periods (140 minutes) / Student-centred

next

Instructions:

- Click on the text boxes below to proceed with the lesson- Click on the Microsoft Word and Microsoft Excel icons to do the tasks

quitThe Lee Family ProblemThe Lee Family Problem

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

introductionback

John, you have been listening to the hi-fi for hours, no

wonder our electricity bill is so high!

Hmmm...I don’t think I am the only culprit here.

Mum has been

watching TV throughout the night

with all the lights on.

The Lee Family was having a family conference during their dinner time…

Yes, you should listen to your mum. Furthermore, whenit is raining, you shouldn’tuse the air conditioner. This will save us a huge amount on the electricity bill

next

Mrs LeeMrs Lee

Mr LeeMr Lee

John LeeJohn Lee

quit The ChallengeThe Challenge

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

introductionback

You will help the Lee family solve their conflict.

Help them reduce their electricity bill and find out who actually consumes the most electricity.

next

back to Lee Family

problem

quitGroundwork for the Groundwork for the ChallengeChallenge

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

introduction

back to Lee Family

problemback

Before you proceed to the tasks,let’s go through some concepts on power, energy and cost of electricity.

next

quitWhat is Power?What is Power?

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

Power is the rate of electrical energy used. Its SI unit is watts ( W ).

However, a commonly used unit for the calculation of household electricity usage is kilowatts ( kW ).

1 kW = 1000W

introductionback next

back to Lee Family

problem

quitWhat is Energy?What is Energy?

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

Energy is the electrical energy used within certain amount of time. Its SI unit is joules ( J ). But a commonly used unit for the calculation of household electricity usage is kilowatts hour ( kWh ).

introductionback next

back to Lee Family

problem

1kWh = Energy used at rate of 1000 watts in 1 hour1kWh = Energy used at rate of 1000 watts in 1 hour

quitHow to know the amount of How to know the amount of Electricity used?Electricity used?

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

Every home has a meter that records the electrical energy used by the household. The display shows the units of electricity used.

Electrical energy consumed (kWh) = Power (kW) X Time (h)

introductionback next

back to Lee Family

problem

quitHow to calculate the How to calculate the Cost of Electricity?Cost of Electricity?

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

The cost is calculated using the following formula:

Currently, the cost of 1 unit of electricity in Singapore is 17.21cents.

introductionback next

back to Lee Family

problem

Cost of Electrical Energy = Electrical Energy consumed X Cost per unit

Cost of Electrical Energy = Electrical Energy consumed X Cost per unit

quitAn Electricity BillAn Electricity Bill

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

To know more about your electricity bill, visit the website below:

introductionback next

http://www.cansupply.com.sg/utilities_form_rollover_new.htmhttp://www.cansupply.com.sg/utilities_form_rollover_new.htm

back to Lee Family

problem

quitWhy must we save Why must we save Energy? Energy?

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

To explore the importance of saving energy,

let’s go to this website :

Can you list 3 reasons for saving energy

after surfing the website?

introductionback next

http://www.ase.org/consumer/didyouknow/

http://www.ase.org/consumer/didyouknow/

back to Lee Family

problem

quit The Tasks…The Tasks…

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

Task Task 1

2

3

TaskTask

TaskTask

Now, you are all equipped to solve the Lee family problem!

You will need to go through the 3 tasks one by one

introductionback next

back to Lee Family

problem

quit

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

1 2 3

You are at Task You are at Task

First, let’s get familiar with the power usage of basic household electrical appliances.

Get a partner. Together, the two of you are complete Task 1.Try to match the values. Raise your hand when you have finished it for further instructions on checking the correct answer. introductionback next

back to Lee Family

problem

Microsoft Excel Worksheet

quit

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

2 3

You are at Task 2 You are at Task 2

Once again, with your partner, answer the questions in the worksheet. After completing the task, print out the worksheet.

1

introductionback next

back to Lee Family

problem

Microsoft Word Document

quit

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

2 3

You are at Task You are at Task

Finally, here is the last hurdle - Task 3...

Again in pairs, come up with measures to reduce the amount of electricity used by the Lee family. Calculate the new monthly electricity bill if all your measures were implemented. Type your answer in the worksheet and print it out.

1

introductionback next

back to Lee Family

problem

Microsoft Word

Document

quitReviewReview

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

Are you satisfied with the new reduced electricity bill?

introductionback next

YESYES NONO

back to Lee Family

problem

quit

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

introductionback

2

3

TaskTask

TaskTask

Do not despair, you still have another chance to make amendment.

Go through task 2 and task 3 again to help the Lee family reduce electricity cost.

back to Lee Family

problem

quit

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

You have not only helped the Lee family but Singapore as well, because precious resources are saved for the country.

introductionback next

back to Lee Family

problem

quitCreditsCredits

tem

plat

e de

sign

ed b

y je

nnife

r w

ong

<je

nnw

ong8

8@ho

tmai

l.com

> c

opyr

ight

© 2

000

NIE

quit

Created by:Wee Yee Yun

Tan Joy

Tutor:Ms Tang Buay Choo

back

http://www.clipsahoy.com/index.htmlhttp://www.clipsahoy.com/index.html

http://antwrp.gsfa.nasa.gov/apod/ap960916.htmlhttp://antwrp.gsfa.nasa.gov/apod/ap960916.html

http://www.discoveryschool.comhttp://www.discoveryschool.com

http://www.cansupply.com.sghttp://www.cansupply.com.sg