SLAF Officer Cadet Selection Exam cheat sheet

Quadratic formula: for ax² + bx + c = 0, x = [−b ± √(b² − 4ac)] / 2a; the discriminant b² − 4ac decides two, one, or no real roots.

Sum of an arithmetic series: S = (n/2)(2a + (n−1)d); sum of a geometric series: S = a(1 − rⁿ)/(1 − r) for r ≠ 1.

Pythagorean triples to recognise instantly: 3-4-5, 5-12-13, 8-15-17, 7-24-25 and their integer multiples.

Area formulas: triangle = ½ × base × height; circle = πr²; trapezium = ½(a + b)h; sector = (θ/360)πr².

Speed–distance–time: speed = distance ÷ time; convert km/h to m/s by multiplying by 5/18.

Simple interest I = PRT/100; compound amount A = P(1 + R/100)^T; average = sum of values ÷ number of values.

Logarithm rules: log(xy) = log x + log y; log(x/y) = log x − log y; log(xⁿ) = n log x.

Probability of an event = favourable outcomes ÷ total equally likely outcomes; P(not A) = 1 − P(A).

Subject–verb agreement: singular subjects take singular verbs; phrases between subject and verb ("the list of items") do not change the number.

Neither/nor and either/or take a verb agreeing with the nearer subject: "Neither the pilots nor the engineer was present."

Active to passive: object becomes subject, verb becomes be + past participle, agent introduced by "by" - "The crew checked the tyres" → "The tyres were checked by the crew."

Reported speech shifts tense back one step: present → past, past → past perfect; time words shift (now → then, tomorrow → the next day).

Conditionals: first (if + present, will + base), second (if + past, would + base), third (if + past perfect, would have + past participle).

Commonly confused pairs: affect (verb) / effect (noun); principal (chief) / principle (rule); stationary (still) / stationery (paper).

Prepositions of time: "in" for months, years, seasons; "on" for days and dates; "at" for clock times.

Punctuation rule: a comma splice (two independent clauses joined by a comma) is an error; use a full stop, semicolon, or conjunction.

Sri Lanka is an island in the Indian Ocean, separated from India by the Palk Strait and Gulf of Mannar; its legislative capital is Sri Jayawardenepura Kotte and its commercial capital is Colombo.

The official languages of Sri Lanka are Sinhala and Tamil, with English as the link language; the currency is the Sri Lankan rupee.

Sri Lanka's highest peak is Pidurutalagala; its longest river is the Mahaweli; the central highlands and Sinhala wildlife reserves are UNESCO World Heritage sites.

The United Nations was founded in 1945 and has its headquarters in New York; its principal organs include the General Assembly and Security Council.

The Commonwealth is a voluntary association of mostly former British territories; its secretariat is in London and heads of government meet at CHOGM.

Aviation bodies: ICAO (Montreal) sets standards and recommended practices; IATA (Montreal) is the airline trade association; the Convention on International Civil Aviation was signed at Chicago in 1944.

Time zones: the prime meridian is 0° longitude at Greenwich; Earth rotates 15° of longitude per hour, so one hour of time difference equals 15°.

For current-affairs items, verify the date, office-holder and source at the time of the exam; office-holders and event dates change and should never be assumed from memory.

Number series: check differences first, then ratios, then alternating or two-interleaved series, then squares/cubes ± constant.

Coding–decoding: write the alphabet with positions 1–26; the reverse position of a letter equals 27 minus its forward position.

Blood relations: draw a family tree with gender marks and vertical parent–child links; "brother of my father" is uncle, "son of my sister" is nephew.

Direction sense: fix north upward, apply each turn as a rotation (right = clockwise 90°), and compute the final displacement with Pythagoras.

Syllogism: a conclusion follows only if it is true in every diagram consistent with the premises; "some A are B" does not imply "some B are A" fails - it does convert.

Analogy and odd-one-out: identify the single relation (function, part–whole, degree, category) and test every option against it.

Seating arrangement: place fixed-position clues first, then apply left/right constraints; in a row facing north, a person's left is the solver's left.

Clock and calendar: the minute hand gains 5.5° per minute on the hour hand; a normal year shifts the weekday by one, a leap year by two.

Newton's second law: F = ma; weight W = mg with g ≈ 9.8 m/s²; momentum p = mv and is conserved in collisions with no external force.

Kinematics: v = u + at; s = ut + ½at²; v² = u² + 2as.

Work = force × distance in the direction of force; power = work ÷ time; kinetic energy = ½mv²; gravitational potential energy = mgh.

Ohm's law: V = IR; power P = VI = I²R = V²/R; resistors in series add, in parallel 1/R = 1/R₁ + 1/R₂.

Pressure in a fluid: P = ρgh; atmospheric pressure at sea level is about 101.3 kPa; buoyancy equals the weight of displaced fluid (Archimedes).

Speed of light in vacuum c ≈ 3 × 10⁸ m/s; speed of sound in air ≈ 343 m/s at 20 °C and rises with temperature.

Lift on a wing arises from the pressure difference between lower and upper surfaces, described by Bernoulli's principle and circulation; lift increases with air density, speed squared and wing area.

Heat transfer occurs by conduction (solids), convection (fluids) and radiation (no medium needed); latent heat Q = mL changes state at constant temperature.

Atomic number = number of protons; mass number = protons + neutrons; isotopes have equal protons but different neutrons.

Mole concept: one mole contains 6.022 × 10²³ particles; moles = mass ÷ molar mass; at STP one mole of gas occupies 22.4 L.

pH scale: pH = −log[H⁺]; pH below 7 is acidic, 7 neutral, above 7 basic; each unit is a tenfold change in hydrogen-ion concentration.

Acid + base → salt + water (neutralisation); acid + metal → salt + hydrogen gas; acid + carbonate → salt + water + carbon dioxide.

Periodic trends: atomic radius decreases across a period and increases down a group; electronegativity and ionisation energy increase across a period.

Oxidation is loss of electrons and reduction is gain (OIL RIG); oxidising agents are themselves reduced.

Balancing equations conserves atoms of each element; the ideal gas law is PV = nRT with R = 8.314 J/(mol·K).

Common gases and tests: hydrogen burns with a pop; oxygen relights a glowing splint; carbon dioxide turns limewater milky.

The four forces on an aircraft in flight are lift, weight, thrust and drag; in steady level flight lift equals weight and thrust equals drag.

Angle of attack is the angle between the wing chord line and the relative airflow; exceeding the critical angle causes a stall, which is a loss of lift, not an engine failure.

The four-stroke piston cycle is induction, compression, power and exhaust; the propeller converts engine torque into thrust.

Primary flight controls: ailerons roll, elevator pitches, rudder yaws; flaps increase lift and drag for take-off and landing.

Altimeter setting: QNH gives altitude above mean sea level, QFE gives height above a reference point, QNE (standard 1013.25 hPa) is used above the transition altitude.

Human factors: hypoxia symptoms worsen above about 10,000 ft without supplemental oxygen; spatial disorientation occurs when visual cues conflict with the balance organs.

The atmosphere is layered troposphere, stratosphere, mesosphere, thermosphere; temperature falls with height in the troposphere at about 2 °C per 300 m (lapse rate).

Air traffic control clearances are read back in full; the phonetic alphabet (Alpha, Bravo, Charlie …) and numerals (niner, tree, fife) reduce mishearing.

Cardiovascular endurance is trained by sustained aerobic work at roughly 60–80 % of maximum heart rate; estimated maximum heart rate ≈ 220 − age in years.

The FITT principle: Frequency, Intensity, Time and Type are the four variables used to structure and progress any training programme.

Progressive overload means gradually increasing training stress; the SAID principle states the body adapts specifically to the demands imposed on it.

Muscular strength is built with low repetitions and high load; muscular endurance with high repetitions and low load.

The Borg rating of perceived exertion runs from 6 to 20, where 6–8 is very light and 17–20 is very hard; it correlates with heart rate.

Warm-up raises muscle temperature and reduces injury risk; cool-down aids venous return and reduces blood pooling after exercise.

Hydration and heat: sweat losses of 1 kg equal roughly 1 litre of fluid; dehydration of 2 % body mass impairs endurance performance.

Body mass index = mass (kg) ÷ height (m)²; a value of 18.5–24.9 is conventionally classified as normal.

Leadership styles: autocratic (decision retained by the leader), democratic (shared decision-making), laissez-faire (minimal direction); situational leadership selects style by follower maturity and task urgency.

The leadership process is direction, motivation, coordination and control; a leader sets the objective, a manager administers resources toward it.

Mission command delegates authority within a stated intent, so subordinates can act when communication fails.

A combat order follows the sequence: situation, mission, execution, administration and logistics, command and signal.

Team development passes through forming, storming, norming and performing; conflict often peaks at storming and must be resolved, not suppressed.

Grievance and discipline are separate processes: a grievance addresses a complaint by a subordinate, discipline addresses a breach of rules.

Feedback is effective when it is specific, timely, behavioural and followed by an agreed action; praise in public, correct in private.

Morale rests on purpose, confidence in leadership, welfare and training; a leader's example is the strongest single influence on unit cohesion.

Assessment centres rate candidates against defined competencies using multiple assessors, multiple exercises and structured rating scales to improve reliability.

Behavioural (competency-based) interviews assume past behaviour predicts future performance; answers are structured as Situation, Task, Action, Result.

A structured interview scores every candidate against the same pre-set questions and anchored rating scales, reducing interviewer bias.

Common rating errors: the halo effect (one good trait colours all ratings), central tendency (avoiding extremes), and the similar-to-me bias.

Group exercises assess cooperation, influence and listening; dominating the group or staying silent both score poorly.

Integrity questions test consistency between stated values and examples given; rehearsed answers usually lose coherence under follow-up probes.

First impressions form within seconds and are hard to reverse; grooming, punctuality and clear speech are assessed from the moment of arrival.

Stress and situational questions test composure: acknowledge the pressure, state a decision rule, then give the action you would take.