1.6 Keep Records — and Expect New Questions

A scientist’s notebook is part of the experiment. While frying puris, you would jot down everything: Did the oil splatter? Smell? Smoke? Which puris puffed, and how fast? These notes are your raw data. Without them, you are relying on memory — and memory edits the truth.

And here is the beautiful part: one round of experiments almost always raises new questions. Do puris puff better made fresh or from stored dough? What happens if I prick a tiny hole before frying? Each answer hands you the next question. That is the loop turning again.

Science Isn’t Finished You might assume scientists fully understand something as everyday as a puffing puri. They don’t! The detailed physics of how the trapped water turns to steam and lifts the dough is still not completely worked out. Many of the most ordinary things around you hide questions no one has answered yet — which means there is plenty left for you to investigate.

Worked Example 3

The whole loop, start to finish. Aarav notices his phulka puffed beautifully one day and stayed flat the next.

  1. Observe: sometimes the phulka puffs, sometimes it stays flat.
  2. Question: does pressing the dough flatter and more evenly help it puff?
  3. Predict: an even thickness traps steam better, so it should puff more reliably.
  4. Experiment: make several phulkas, roll some evenly and some unevenly, keep flame, flour and size the same.
  5. Record: note which puffed and how fully.
  6. Explain: if the even ones puff more often, evenness matters — and the next question appears: how even is “even enough”?

Figure it Out — The Investigator’s Method

Practice

  1. Which of these are scientific (testable) questions? (i) Which song is the best? (ii) Does salt dissolve faster in hot water than cold? (iii) Is honey healthier than sugar to taste? (iv) Does a heavier ball roll down a ramp faster?
  2. In the experiment “Does a fan dry wet clothes faster?”, name the variable you change, the variable you measure, and two variables you should keep the same.
  3. Rohit tests whether music helps plants grow. He plays music to Plant A in his sunny bedroom and keeps silent Plant B in the cool garage. Give two reasons his test is unfair.
  4. Turn this wondering into a sharp scientific question: “Ice seems to melt really fast on metal.”
  5. Why do scientists keep written records during an experiment instead of trusting memory? Give one reason in your own words.
  1. (ii) and (iv) are scientific — both can be settled by an experiment with something to change and something to measure. (i) and (iii) are about taste/opinion and cannot be decided by experiment.
  2. Change: whether the fan is on or off (or fan speed). Measure: the time for the clothes to dry. Keep the same: the same clothes, same amount of water in them, same room, same starting time — any two of these.
  3. Two variables changed besides the music: the light (sunny bedroom vs garage) and the temperature (warm vs cool). So any difference could be due to light or temperature, not the music.
  4. A possible question: “Does an ice cube melt faster on a metal plate than on a wooden plate of the same temperature?” (You change the surface, measure the melting time, keep ice size and room the same.)
  5. Memory is unreliable and tends to remember what we expect; written notes capture exactly what happened — including surprises like splattering or smell — so the evidence stays honest. (Any sensible reason accepted.)