Rahul DubeyDropperSample· 3d ago
Fridge door open makes the room hotter, COP of 9 seems odd, and fridge cooling lowers entropy. Does it break the second law?
A third-attempt student asking a first-principles question late at night.
#neet
Stories and questions with this tag.
- Kavya NaikDropperSample· 3d ago
Population vs community vs ecosystem vs biome, and what "emergent properties" means at each level of biological organisation
Revising the Living World for the third or fourth time and I realise I only memorised the ladder instead of understanding it. NCERT says living organisms show a hierarchy: cellular organelles, cells, tissues, organs, org
- Kavya NaikDropperSample· 3d ago
Arrhenius: my Ea for 'rate doubles per 10 K' is 53.6 kJ but the book says 52.9. Who is right?
Also what does the factor P actually do and what does a catalyst change?
- Kavya NaikDropperSample· 4d ago
Why did Mendel pick the pea plant, and how can you cross a flower that pollinates itself?
Aiyo, amma asked me at breakfast "what did Mendel do?" and I realised my answer was just "peas, tall and dwarf, 3:1". So I decided to go back to the basics of Principles of Inheritance and Variation, which I somehow revi
- Rahul DubeyDropperSample· 4d ago
Third attempt and I still mix up amensalism, commensalism and competition signs. Cleanest way to fix the (+,-,0) table?
Third attempt. I will say it plainly: I know this chapter, and I still lose marks on it because of the sign table. I look at a question like "one species benefits and the other is neither harmed nor benefited" and for a
- Kavya NaikDropperSample· 4d ago
Adrenal cortex layers and hormones vs adrenal medulla: how to remember glomerulosa, fasciculata, reticularis and what each makes?
Amma says I study like I'm trying to eat an elephant in one bite, so today I decided to do only the adrenal gland and nothing else. And it's still messy. From NCERT I have this: the adrenal glands sit on top of the kidne
- Kavya NaikDropperSample· 4d ago
Green chemistry examples in NCERT: which process replaced which (dry cleaning, bleaching, ethanal)? Mixing up the chemicals
Amma says I study chemistry like I'm doing a quiz show, fast but with mistakes 😅. Soil pollution and green chemistry is one of the "easy" last pages that I still get wrong in tests because the examples blur. What I know:
- Ishita GoyalDropperSample· 5d ago
Lucas test turbidity timing for primary, secondary and tertiary alcohols, and why neutral FeCl3 works only for phenol
I'm building my one-page template for alcohols, phenols and ethers distinction tests on top, named reactions below and a few cells are still empty. Lucas test: I know the reagent is conc. HCl with anhydrous ZnCl2. I know
- Lakshmi TripathiDropperSample· 5d ago
ECG waves P, QRS, T: why isn't atrial repolarisation visible? And heart attack vs cardiac arrest vs heart failure
I usually don't post questions, but this chapter has defeated my reading-only method. ECG: P wave, QRS complex, T wave. I know the NCERT lines: the P wave represents the electrical excitation depolarisation of the atria,
- Lakshmi TripathiDropperSample· 6d ago
Brain capacity and diet of Homo habilis, Homo erectus and Neanderthals, my table keeps mixing them up
I read slowly, so I've gone through "Origin and Evolution of Man" three times, and I still muddle the facts. I'm trying to build one table in chronological order and I'd like to check it. My notes: - Dryopithecus and Ram
- Farhan ShaikhDropperSample· 6d ago
Why is heavy water used as a moderator and not normal water? And why isn't hydrogen already the fuel everyone uses?
Revising Hydrogen again 3rd time lol, budget wale notes bhi ab ghis gaye . Two things that I never got logically. 1. NCERT says D 2O is used as a moderator in nuclear reactors. A moderator slows neutrons down. But normal
- Siddharth RaoDropperSample· 8d ago
Rolling down an incline: why does friction not reduce the energy, and which shape reaches first?
I'm repeating, and rotational motion is the chapter I have always handled with formulas, not understanding. This time I want the concept. Pure rolling means v=\omega R for the centre. Total KE =\tfrac12mv^2+\tfrac12I\ome
