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📅 Exam: 30 May 20257 topics · Formula-based · High priority
Imagine pushing a box. Work is done only when the box actually moves. Push a wall and it doesn't move? Zero work done!
F = force, s = distance moved, θ = angle between force and motion direction. If you push straight ahead → θ=0° → cos(0°)=1 → W = F×s
A fast cricket ball has more energy than a slow one. Mass and speed both matter.
A ball held up high has PE. Drop it → PE converts to KE.
g = 10 m/s², h = height from ground
Same work done in less time = more power. Sports car is more powerful than a truck.
Unit = Watt (W). 1 Horsepower = 746 W
A fast cricket ball hurts more than a slow one — that "punch" is momentum. Depends on both mass and speed.
When two objects collide, total momentum before = total momentum after. Nobody creates or destroys momentum.
| Type | KE conserved? | Momentum conserved? |
|---|---|---|
| Elastic | ✅ Yes | ✅ Yes |
| Inelastic | ❌ No | ✅ Yes |
| Perfectly inelastic (stick together) | ❌ No | ✅ Yes |
Think of a water pipe: Voltage = water pressure, Current = water flow, Resistance = pipe thickness. More resistance → less current.
V = Volts, I = Amperes, R = Ohms (Ω)
Series = resistance adds up = less current. Parallel = more paths = more current.
Torque is rotational force. Opening a door — push near the hinge = less torque. Push at the edge = more torque.
Rotational mass — more spread-out mass = harder to spin.
| Shape | Moment of Inertia |
|---|---|
| Ring | mr² |
| Disc | ½mr² |
| Solid Sphere | 2/5 mr² |
| Rod (about center) | 1/12 mL² |
v = wave speed, f = frequency (Hz), λ = wavelength (m)
Node = point that never moves (zero displacement). Antinode = point that moves the most (maximum displacement).
Sound = longitudinal wave. Speed in air ≈ 340 m/s at room temperature. Speed increases with temperature.
Energy can't be created or destroyed. Heat given to gas = increase in internal energy + work done by gas.
| Process | What stays constant |
|---|---|
| Isothermal | Temperature (T) |
| Adiabatic | No heat exchange (Q = 0) |
| Isochoric | Volume (V) |
| Isobaric | Pressure (P) |
Most efficient engine possible. Uses two temperatures (always in Kelvin).
Shine light on a metal → electrons come out. Only works above a minimum frequency. More intensity = more electrons, but higher frequency = more energetic electrons.
h = Planck's constant = 6.63 × 10⁻³⁴ Js
| Type | What is it | Penetration |
|---|---|---|
| Alpha (α) | Helium nucleus | Least (stopped by paper) |
| Beta (β) | Electron | Medium |
| Gamma (γ) | EM wave | Most (needs lead to stop) |
n-type = doped with pentavalent element (extra electrons). p-type = doped with trivalent element (holes). p-n junction = diode = current flows only one way.
5 topics · Memory-based · High priority
Size of atom. Goes LEFT → bigger (more electrons). Goes DOWN → bigger (more shells).
Energy needed to remove an electron. Opposite trend to atomic radius.
How strongly an atom pulls shared electrons toward itself. Fluorine = highest in the entire table.
Ionic: metal gives electron to non-metal (NaCl). Covalent: both share electrons (H₂O). Metallic: sea of electrons in metals.
Electron pairs repel each other → arrange as far apart as possible → gives molecule its shape.
| Molecule | Shape | Bond Angle |
|---|---|---|
| BeCl₂ | Linear | 180° |
| BF₃ | Trigonal planar | 120° |
| CH₄ | Tetrahedral | 109.5° |
| NH₃ | Pyramidal | 107° |
| H₂O | Bent / V-shape | 104.5° |
An ion leaves its spot and squeezes into a gap (interstitial site) within the crystal. Density stays the same. Common in AgCl, AgBr (small cation + large anion).
Equal number of cations and anions go missing from the crystal. Density decreases. Common in NaCl, KCl (similar sized ions).
An electron gets trapped where an anion is missing. This gives the crystal a colour. Example: NaCl heated in Na vapour → turns yellow.
ΔH negative = exothermic (releases heat, e.g. burning). ΔH positive = endothermic (absorbs heat, e.g. melting ice).
Electrochemical cell: chemical energy → electrical energy. Anode = oxidation (loss of electrons). Cathode = reduction (gain of electrons).
Made of C, H, O. Main energy source. Glucose & fructose = monosaccharides. Sucrose & lactose = disaccharides. Starch & cellulose = polysaccharides.
Proteins = amino acids joined by peptide bonds. Enzymes are proteins. DNA stores genetic info. RNA helps make proteins.
Natural: rubber, silk, cellulose. Synthetic: Nylon (polyamide), PVC, Teflon, Bakelite, Terylene (polyester).
5 topics · Formula-focused · Medium priority
log₁₀(100) = 2 means "10 to the power of 2 = 100". Log asks: "what power do I raise the base to, to get this number?"
Rate of change. Speed is the derivative of distance. It tells you how fast something is changing at any moment.
A grid of numbers in rows and columns. A 2×2 matrix has 2 rows and 2 columns.
Cross multiply diagonally and subtract. That's it!
Flip rows and columns. Row 1 becomes Column 1, Row 2 becomes Column 2, etc.
Each term differs by a fixed amount (d). Like 2, 5, 8, 11... → d = 3
Each term is multiplied by a fixed ratio (r). Like 2, 6, 18, 54... → r = 3
A set is just a collection. A = {1, 2, 3}. Empty set = {} = φ.
Takes an input (x) and gives exactly one output (y). Domain = all valid inputs. Range = all possible outputs.
3 topics · Easy marks · Don't skip
| Word | Synonym | Antonym |
|---|---|---|
| Abundant | Plentiful | Scarce |
| Benevolent | Kind | Malevolent |
| Candid | Frank | Deceptive |
| Diligent | Hardworking | Lazy |
| Eloquent | Articulate | Inarticulate |
| Frugal | Thrifty | Extravagant |
| Gloomy | Dismal | Cheerful |
| Hasty | Rash | Careful |
| Impartial | Unbiased | Biased |
| Jovial | Cheerful | Gloomy |
| Lenient | Mild | Strict |
| Meticulous | Careful | Careless |
| Tense | Example |
|---|---|
| Simple present | He runs every day |
| Present continuous | He is running now |
| Simple past | He ran yesterday |
| Present perfect | He has run 5km today |
| Past perfect | He had run before it rained |
❌ He don't know → ✅ He doesn't know
❌ More better → ✅ Better
❌ I seen him → ✅ I saw him
❌ Between you and I → ✅ Between you and me
❌ Less people → ✅ Fewer people
1. Read the questions FIRST, then read the passage looking for those answers.
2. The answer is always IN the passage. Don't use outside knowledge.
3. For "main idea" questions → usually in first or last paragraph.
4. For "tone/attitude" questions → look for feeling words (critical, optimistic, sarcastic).
5. Don't spend more than 4–5 minutes on one passage. Move on if stuck.
2 topics · Logic-based · Easy marks
Find the relationship in the first pair → apply same relationship to the second pair.
Example: Book : Library :: Painting : ?
→ Books are kept in Libraries → Paintings are kept in Galleries ✅
| Type | Example |
|---|---|
| Tool : User | Scalpel : Surgeon |
| Part : Whole | Page : Book |
| Worker : Workplace | Chef : Kitchen |
| Animal : Sound | Lion : Roar |
| Word : Opposite | Day : Night |
| Cause : Effect | Rain : Flood |
| Product : Source | Wool : Sheep |
Find the pattern. Could be +2, ×3, alternating, squares, etc.
Example: 2, 6, 12, 20, 30, ? → differences are 4, 6, 8, 10, 12 → answer = 42
Find what's different — could be category, shape, number pattern.
Example: Apple, Mango, Carrot, Banana → Carrot is a vegetable, rest are fruits.
Always draw a family tree. Don't try to solve in your head.
Example: "A is B's father's only son" → A is B's father → A is B's father.