4 The total amount of energy in the universe is always the same but can be transferred from one energy store to another during an event

Worksheet 5.2: Picture puzzle

WORKSHEET Workshop

Teaching aids:

Worksheet

Procedure:

The studentsdiscuss theirresults in groups. The instruction is: “What did you find in the picture?Which of them produces light, movement or heat (temperature)?” They students can add their results in the table.


object	light	movement	heat
lamp	X		X
car	X	x, (e.g. airing)
air-conditioning		X	X
stove	X		X
fridge		X	X
washing machine	X	X	X
dryer		X	X
television (TV)		X	X

Note: Certain objects may be misjudged. For example, a movement displayed on a television (TV) can be classified as movement (kinetic energy). Here the teacher decides whether to discuss such cases in the class or not (questions: “What exactly is moving there? Do you think it is a “real“movement?”). The understanding of the principle of transferring energy from one energy store to another is not affected by such a misunderstanding.

Reworking during class discussion (with the following central questions): “Why becomes electricity sometimes light and sometimes movement?” If the term energy is not be mentioned: “Which other words do you know for the term electricity?” If the term energy is mentioned during class discussion, it is important to explain that light, movement and heat (temperature) are also energy: “What happens to the electricity?“

In a two-steps approach (sub1&sub2) the law of conservation of energy is introduced using the example of converting electricity in other forms of energy. Since this type of converting is the most common to children, each child should at least be able to find some examples and understand the basic concept with the help of a class discussion.

For younger children, the “basic idea” that electricity is turned into light by the light bulb is adequate. Students in the third and fourth grades can examine how light bulbs and stoves are working. Since the question is directly related to objects known by the children (because they recognized them in the drawing), students with different abilities and knowledge should be able to solve the task –even though at different levels regarding the identified objects.