lesson
Different emissions have different effects
1 · Learn
Carbon dioxide and methane contribute to greenhouse warming, while pollutants such as particulates, sulfur dioxide and nitrogen oxides have other environmental and health effects. One label such as pollution should not hide the different mechanisms.
Climate conclusions use long-term evidence and physical understanding, not a single day's weather. Uncertainty in an estimate does not mean no evidence exists; identify what is uncertain and its range.
2 · Worked example
Reducing visible smoke alone does not establish that carbon dioxide emissions are zero. Different emissions need different measurements.
3 · Your turn
Why does the absence of visible smoke not prove a process has no greenhouse-gas emissions?
Check your answer
Some relevant gases are invisible, so appearance is not a complete emissions measurement.
4 · Apply your learning
Interpret supplied emissions data with units and system boundaries, distinguishing measured values from projections.
Adult guidance and safety
Use supplied evidence and approved models. Practical work needs qualified supervision, risk assessment and suitable equipment. No independent chemical, mains-electricity, radiation or biological-culture experiments. Human biology is general education, not personal medical advice; do not request intimate or health disclosures.
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Check a calculation · Year 5 onward
Use this only when your teacher or adult allows a calculator for the task. Show your thinking first. It does not replace mental or written arithmetic and does not mark your lesson answer.
Powers, roots and trigonometry · Year 7 onward
Use only when the task allows a calculator. Choose one operation at a time and record your working. Trigonometry here always uses degrees (DEG), not radians. Inverse sine, cosine and tangent return an angle, not a reciprocal. Keep exact fractions and π in answers when requested.
Approximate numerical results use up to 12 significant digits. Inverse sine returns −90° to 90°, inverse cosine 0° to 180°, and inverse tangent −90° to 90°; these are principal values, not every possible solution of a trigonometric equation.
My observation notebook
Follow your teacher's approved method and safety instructions. Record the sample or supplied dataset, conditions, measurements with units and uncertainties where appropriate. Distinguish observations from explanations. A described experiment is not permission to carry it out; do not improvise equipment or invent missing results.
Ask your teacher for support with the method and recording. A prediction is what you think might happen; an observation is what you actually see, hear or feel safely.
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