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What does physics study? Physical phenomena
Textbook, pp. 3–5
GoalLearn what physics studies and tell mechanical, heat, electric, light and sound phenomena apart.
New words
physics (from Greek physis, “nature”) · fizikanatural phenomenon · tabiat hodisasimechanical phenomenon · mexanik hodisalight phenomenon · yorug‘lik hodisasi
Explanation
Physics is the science of nature. Falling snow, flowing water, drifting clouds and a burning lamp are all natural phenomena. Physics studies how and why they happen and which laws they follow. Using physics, people built power stations, machines and household appliances. By their signs, phenomena are divided into five groups: mechanical (motion of bodies), heat (warming, melting, boiling), electric, light and sound phenomena. Studying them begins with the structure of matter. In Grade 6 you meet all of them for the first time.
Worked examples
A bicycle moving is a mechanical phenomenon; water freezing is a heat phenomenon; a rainbow appearing is a light phenomenon; the rumble of thunder is a sound phenomenon.
A plastic comb rubbed on hair attracts bits of paper — this is an electric phenomenon.
Class activity
“Phenomenon cards”: the teacher prepares 15 cards with phenomena (for example “snow melting”, “lightning”, “a car driving”). Groups sort them into five types and stick them on a table on the board.
Practice
1
From which language does the word “physics” come and what does it mean?
From the Greek word “physis”; it means “nature”.
2
Which group of phenomena does the melting of ice cream belong to?
Heat phenomena.
3
Which is a mechanical phenomenon: a candle burning or a bus driving?
A bus driving — because the body changes its position.
4
Why is knowing the laws of nature useful to people?
If we know the laws, we can use nature more effectively and build machines that make work easier.