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🇮🇳 CBSE Class 10 · flashcards
CBSE Class 10 Science Flashcards
66 question-and-answer cards covering Science as it is examined in CBSE Class 10. 24 of them are printed below, taken from across the deck — no signup, no paywall on the preview.
24 sample cards from the Science deck
Sampled from the end of the deck, so these are different cards from the ones shown on the syllabus page.
Write the mirror formula and the magnification formula for a spherical mirror.
Mirror formula: 1/v + 1/u = 1/f. Magnification: m = -v/u = height of image / height of object.
Define refractive index and give Snell's law.
Refractive index n = speed of light in vacuum / speed in medium. Snell's law: sin i / sin r = constant (refractive index of second medium w.r.t. first).
Write the lens formula and state the power of a lens with its SI unit.
Lens formula: 1/v - 1/u = 1/f. Power P = 1/f (in metres), SI unit is dioptre (D).
What happens to a ray of white light when it passes through a glass prism?
It bends towards the base and splits into its seven constituent colours (VIBGYOR) - this dispersion happens because different colours bend by different amounts.
Why is the sky blue and why does the Sun appear red at sunrise/sunset?
Blue sky: shorter blue wavelengths are scattered more by air molecules (Rayleigh scattering). Red Sun: at sunrise/sunset light travels longer through atmosphere, so most blue is scattered away leaving red.
Name the defect of vision in which a person cannot see distant objects clearly and how it is corrected.
Myopia (short-sightedness); image forms in front of the retina. Corrected using a concave (diverging) lens of suitable power.
What is the power of accommodation of the eye and which part is responsible?
The ability of the eye lens to adjust its focal length to focus objects at different distances. The ciliary muscles change the curvature/thickness of the eye lens.
State Ohm's law and write its formula.
At constant temperature, the current through a conductor is directly proportional to the potential difference across it. V = IR (where R is resistance).
How does resistance depend on length and area of cross-section of a wire? Give the formula.
R = rho x L / A. Resistance is directly proportional to length (L) and inversely proportional to area of cross-section (A); rho is resistivity.
Write the formula for electric power in three forms.
P = VI = I^2 R = V^2 / R. SI unit is watt (W); 1 unit of electricity = 1 kilowatt-hour (kWh).
State the rule used to find the direction of magnetic field around a straight current-carrying conductor.
Right-hand thumb rule: if the thumb of the right hand points in the direction of current, the curled fingers show the direction of the magnetic field lines.
State Fleming's left-hand rule and what it is used for.
Stretch thumb, forefinger, and middle finger of the left hand perpendicularly: forefinger = field, middle finger = current, thumb = force/motion. Used to find force on a current-carrying conductor in a magnetic field (electric motor).
What is electromagnetic induction and which rule gives the direction of induced current?
Production of induced current in a coil by changing the magnetic field around it. Fleming's right-hand rule gives the direction of induced current (used in generators).
What are the colours of live, neutral, and earth wires in domestic wiring, and the purpose of the earth wire?
Live = red/brown, Neutral = black/blue, Earth = green (or yellow-green). The earth wire is a safety measure that carries leakage current to the ground.
What is a good source of energy? Name any two renewable and two non-renewable sources.
A good source supplies a large amount of energy economically, safely, and is easy to store/transport. Renewable: solar, wind. Non-renewable: coal, petroleum.
What is biogas, what is its main component, and what is the slurry used for?
Biogas is produced by anaerobic decomposition of biomass; its main component is methane (CH4). The leftover slurry is used as an excellent manure/fertiliser.
What is a food chain and what are the trophic levels?
A series of organisms feeding on one another transferring energy. Trophic levels: producers (plants), primary consumers (herbivores), secondary and tertiary consumers (carnivores), and decomposers.
State the 10 percent law of energy flow in an ecosystem.
Only about 10% of the energy at one trophic level is transferred to the next level; the rest is lost as heat. This limits food chains to 3-4 levels.
Differentiate between biodegradable and non-biodegradable substances with one example each.
Biodegradable: broken down by microbes (e.g. paper, food waste). Non-biodegradable: not decomposed by microbes (e.g. plastic, DDT, glass).
How is the ozone layer beneficial and what chemical is mainly responsible for its depletion?
The ozone layer absorbs harmful ultraviolet (UV) radiation from the Sun. Chlorofluorocarbons (CFCs) are mainly responsible for its depletion.
What do the three R's stand for in management of natural resources?
Reduce, Reuse, and Recycle - reducing consumption, reusing items, and recycling materials to conserve natural resources.
What are the advantages and one disadvantage of building large dams?
Advantages: irrigation, electricity generation, water supply. Disadvantages: displacement of people, submergence of forests/land, and loss of biodiversity.
What is rainwater harvesting and name a traditional water harvesting method.
Collecting and storing rainwater for later use and for recharging groundwater. Traditional methods include khadins, tanks, bawris/baolis, and check dams.
Why is the conservation of forests and wildlife important, and who are the stakeholders?
To maintain biodiversity and ecological balance. Stakeholders: local people dependent on forests, the Forest Department, industrialists, and wildlife/nature enthusiasts.
What this deck covers
The Science deck follows the CBSE Class 10 Science syllabus — 5 chapters and 19 topics — so questions land on material that is genuinely examinable rather than trivia around it. That works out to roughly 13.2 cards per chapter.
Answers are written to be recallable, not just readable — averaging about 151 characters, which is long enough to carry the reasoning and short enough to say out loud.
A deck like this earns its keep on the second and third pass. Read the syllabus first so you know the shape of the subject, then use the cards to find the specific facts that have not stuck.
Science flashcards FAQ
How many Science flashcards are in this CBSE Class 10 deck?
66 cards. This page previews 24 of them, sampled evenly across the deck so you can judge the difficulty before installing anything.
Are these CBSE Class 10 flashcards free?
Yes. The preview here is free to read with no signup, and the full 66-card deck is free inside the Examius app.
What do the Science cards cover?
They follow the CBSE Class 10 Science syllabus — 5 chapters and 19 topics — so the questions track what is actually examinable.
How should I use these flashcards?
Read the syllabus first so you know the shape of the subject, then drill the deck. Examius schedules each card with spaced repetition, so cards you keep missing come back sooner and ones you know drift further apart.