Practice Test 5

Question Paper

Questions 21-25

Circle the correct letter A–C.

21 Lyn is having difficulty completing her project because

A she doesn’t have enough information.
B she can’t organise her presentation.
C she doesn’t have enough time.

22 Her presentation is going to focus on

A solar power in America.
B solar-powered water heaters.
C alternative energy technology.

23 Why does Lyn think we should be looking for alternative sources of energy?

A Fossil fuels are expensive.
B Fossil fuels have an impact on the environment.
C Fossil fuels are limited.

24 Solar power is a good form of alternative energy because

A it can be harnessed with simple technology
B it is infinite
C it can be applied equally well in any country.

25 Which graph best indicates what Lyn is describing?

Questions 26 to 30

Label the following diagram USING NO MORE THAN TWO WORDS AND / OR A NUMBER

26. ....................

27. .................

28. ....................

29. ......................

30. ........................

Transcript Solution

Mark

Hi Lyn. How’s your project coming along?

Lyn

Oh, not very well. I’ve got all the information, but I can’t seem to organise it into a presentation.Q10

Mark

Well you’d better hurry. You only have one more week.

Lyn

Yes, that’s OK, it’s just that…ohh….(sound of desperation)

Mark

Well, why don’t you try your presentation on me. Maybe l can help?

Lyn

Really? Great! OK, well I’ve chosen solar power for my subject, and I’m going to talk specifically about domestic water heating.Q22 You know, like the ones popular in America. I’ve got some facts here…

Mark

That’s good, but just start your presentation from the beginning.

Lyn

Oh, right. Here we go then. There are many reasons why we should be looking elsewhere for energy sources. As most people are aware, fossil fuels and other such non-renewable sources are by definition finiteQ23, so something needs to be in operation soon. Currently, there are a number of alternative energy sources available which can, with a little preparation, be used to provide for a significant part of our domestic energy requirements. In this presentation I am focusing solar power and its application as a domestic water heater. As a renewable energy source, solar power is in many ways ideal. The amount of the sun’s energy which reaches the Earth every minute exceeds the energy that the global population consumes in a year. Although scientists argue that it is not finite, sunlight is certainly a long-lasting resource which is not depleted through use, and solar power converters use this energy without needing any complex moving parts.Q24 Once collected and stored, solar energy can be used for many purposes, but it is becoming increasingly popular as a domestic heating source. Generally, a building that is heated by solar power will have its water heated by solar power well, and this has even worked in areas that are not exposed to long hours of as direct sunlight such as the United Kingdom, although not so well as in warmer climates (long pause)

Mark

Why have you stopped?

Lyn

Well, that’s all I’ve got so far.

Mark

Well, start by talking about how effective it is.

Lyn

Oh, OK. Well, there are a number of factors that influence how efficient solar power can be. The first, obviously, is the amount of sunlight, and this is dependent on season, time of day, and climate. Although the UK has something of a bad reputation for sunshine, it is actually quite productive during some parts of the year. Given a sufficient size of solar panel and water storage tank, solar power can provide all of our water-heating requirements in June and July, and even provide the majority until October.

B

C

Ans- A – this answer seems to cause a lot of confusion, so to clarify, the speaker says ‘can provide the majority until October’ – that means you are looking for a graph where October DOES NOT supply the majority (e.g. 50% or more), and that leaves only Graph A.

' >Q25 From October to the end of the year this figure December is the least productive, being able to supply less than 5% the average household’s hot water requirement. It is at this point that solar power needs to be supplemented with a more traditional form of heating. From January, solar power becomes more effective at a rate of about 20% per month, although this rise decelerates to around 18% by May.

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Mark

Now say something about this water heater Do you have any information about that?

Lyn

Yes, I’ve got an illustration of a water tank here.

Mark

That’s good, but you’ll have to describe it.

Lyn

Right. Well, the ideal water tank in the UK has a capacity of 45 to 50 litres, to heat the least 40 litres

' >Q26to be effective. The solar coil

' >Q27is put in the bottom of the tank to heat the water. Now, remember that solar water will not get quite as hot as fossil fuel water heaters. The bottom half of the tank is normally 20 degrees,

' >Q28and this is why it is important not to have a tank that is too large as it would take too much energy to heat. In this illustration, it rises to 40 degrees from halfway up. Don’t forget hot rises, so the top third of the tank is the hottest, and reaches an average temperature of 65 degrees.

' >Q29