Formative assessment marking key Energy module quiz

Commonwealth of Australia, 2003 1

This marking key is constructed so that it can be used for formative purposes. Possibleanswers to each question are provided. These answers show different levels of conceptualdevelopment from low (*), medium (**) to high (***). This information can be used in aformative manner to match students’ levels of conceptual development to activities ofappropriate conceptual challenge designated by one, two or three stars. Some questionsonly provide opportunity for students to respond at the lower levels of conceptualdevelopment.

1. What is energy? Write one or two sentences to explain your meaning for the termenergy.

Level ofconceptual

developmentTypical student response at this level

Energy makes things happen or energy is the capacity to do work.

Work can be done/things can happen when there is sufficientenergy and energy is transformed/changed to another form as thework is done.

2. For each of the following statements about energy, indicate whether the statement istrue or false, and then write a sentence to explain why.a. I get my energy from sleeping. b. Ultimately, all of our energy comes from the Sun.

Level ofconceptual

developmentTypical student response at this level

(a) False. People get energy from their food.

(b) True.

(c) False. Energy to do work is released from food by respiration.

(d) True. Plants use energy from the Sun to grow, plants provideour food energy, and dead plants have turned into coal, gasand oil over long periods of time.

Formative assessment marking key Energy module quiz

Commonwealth of Australia, 2003 2

3. Sunglasses protect our eyes from the Sun.a. Use the diagram below to show and explain how sunglasses reduce the amount of

solar radiation that reaches our eyesb. Solar radiation consists of three types of electromagnetic radiation.

i. What are they and what effect do they have on our eyes? ii. What effect do sunglasses have on each type of radiation?

Level ofconceptualdevelopment

Typical student response at this level

(e) Solar radiation can be reflected off sunglasses, or it can beabsorbed by the lens which reduces the amount transmittedthrough the lens to the eye.

(f) i Solar radiation consists of visible light which helps us see,infrared which has a heating effect and ultraviolet which candamage tissues and cause cancer.

(b) ii Sunglasses need to reflect or absorb infrared and ultraviolet toprotect the eyes from damaging radiationSunglasses need to allow visible light to reach the eyes so thatwe can see. In very bright light, sunglasses should reduce theamount of visible light reaching our eyes to reduce glare

4. Three students were investigating the effect of different solar heaters on raising thetemperature of 100 mL of water in one hour. The students’ results are presented in thetables below.a. Which set of results do you think is most reliable? Explain why, giving at least two

reasons.b. To ensure these were fair tests, which variables would have to be controlled? Why?

Level ofconceptual

developmentTypical student response at this level

(a) Student 3’s results would be more reliable because s/hecollected more results/data

(b) The amount of water and the time

(a) Student 3’s results are more reliable than Student 1 as s/he didrepeat trials which gives more data, and the variation betweenStudent 3’s repeat trials is less than that for Student 2 whichindicates there is less error

(b) The amount of water and the time could both affect the changein temperature so they must be kept the same to be sure it wasonly the type of solar heater that affected the temperature

Formative assessment marking key Energy module quiz

Commonwealth of Australia, 2003 3

5. Draw an energy flow diagram for:a. Water being heated in a kettle with a whistle on a gas stove

Level ofconceptual

developmentTypical student response at this level

Flow chart includes most steps and some sources of waste energy

Flow chart includes most steps and sources of waste energy andarrows give some indication of amount of energytransferred/transformed

b. Water being heated in an electric kettle which has no whistle

Level ofconceptual

developmentTypical student response at this level

Flow chart includes all steps and the main source of waste energy

Flow chart includes all steps, the main source of waste energy andthe arrows give some indication of the amount of energytransferred/transformed

Chemicalpotentialenergy of gas

Heatenergy offlame

Heat energyof kettle

Heat energyto air

Heat energyto air

Electricalenergy

Heat energyof heatingelement

Heat energy ofwater andsteam

Heat energyto kettle andair

Heat energyof water andsteam

Formative assessment marking key Energy module quiz

Commonwealth of Australia, 2003 4

c. i. Which of these would be more energy efficient? ii. Explain what we mean by efficiency. iii. Why is the one method of heating water more efficient than the other?

Level ofconceptual

developmentTypical student response at this level

i. The electric kettle is more efficient.ii. An efficient kettle uses most of the available energy for heatingwater.

iii. The electric kettle is more efficient than the gas kettle as it hasless energy wasted as heat to the air or as sound from the whistle.

ii. Efficiency refers to the amount of energy transferred ortransformed into useful energy for the intended purpose relative tothe amount of energy transformed into waste energy that is notused for the intended purpose.

6. What are the environmental benefits of using hydroelectricity, wind energy and solarenergy compared to coal, gas and petrol?

Level ofconceptual

developmentTypical student response at this level

When coal, gas and petrol are burned they produce pollution;hydro, wind and solar energies do not produce pollution.

Coal, gas and petrol are a limited resource whereas hydro, windand solar energies are renewable and don’t get used up.

Coal, gas and petrol are a limited resource whereas hydro, windand solar energies are renewable and don’t produce carbondioxide which contributes to the greenhouse effect and other gaseswhich cause air pollution.