Delhi Police Head Constable Ministerial cheat sheet

Delhi Police is the police force of the National Capital Territory of Delhi; it functions under the Ministry of Home Affairs, Government of India, and its headquarters is at Jai Singh Road, New Delhi.

The Delhi Police Commissioner is an IPS officer appointed by the central government; the force is divided into ranges and districts, each headed by a Special Commissioner or Deputy Commissioner of Police.

The Indian Constitution came into force on 26 January 1950; it was adopted by the Constituent Assembly on 26 November 1949, a date now observed as Constitution Day.

Fundamental Rights are in Part III (Articles 12-35); the Right to Constitutional Remedies (Article 32) was called the 'heart and soul of the Constitution' by Dr. B. R. Ambedkar.

The Preamble declares India a sovereign, socialist, secular, democratic republic; the words 'socialist', 'secular' and 'integrity' were added by the 42nd Amendment, 1976.

The President is the constitutional head of state elected indirectly; the Prime Minister heads the Council of Ministers, and the real executive power rests with the Council of Ministers.

Key dates: Quit India Movement 1942, Jallianwala Bagh massacre 13 April 1919, Indian National Congress founded 1885, first war of independence 1857, India independent 15 August 1947.

National symbols: national bird Indian peacock, national animal Bengal tiger, national flower lotus, national fruit mango, national river Ganga, national sport-hockey is officially recognised as the national game.

Static science facts: the SI unit of force is the newton, of pressure the pascal, of power the watt; the chemical symbol for sodium is Na and for potassium K; the pH of pure water is 7.

Alphabet positions: A=1 to Z=26. The opposite-letter pair rule gives A-Z, B-Y, C-X etc., so the opposite of a letter at position n is at position 27-n.

Coding-decoding: identify the shift pattern (+1, -2, alternating) or the reversal/opposite-letter rule before applying it to the target word; verify with at least two letters.

Series completion: check successive differences first, then ratios, then squares/cubes (1, 4, 9, 16... or 1, 8, 27...), then alternating interleaved series.

Blood relations: draw a small family tree using symbols; vertical line for parent-child, horizontal for siblings, and mark gender explicitly. 'Brother of my father' = uncle; 'son of my sister' = nephew.

Direction sense: fix north at the top; use Pythagoras (shortest distance = square root of sum of squares of the two legs) for right-angled displacement problems.

Syllogism: in 'All A are B' the A circle lies inside B; 'No A is B' means disjoint circles; 'Some A are B' means overlap. Only conclusions true in every possible diagram are valid.

Odd-one-out and classification: test for a shared property such as all primes, all perfect squares, all state capitals, or all units of measurement; the odd item breaks the property.

Analogy: determine the relation type first (worker-tool, cause-effect, part-whole, synonym, antonym, unit-conversion) and apply the same relation to the options.

Ranking and seating: for linear arrangements fix the extreme positions first; for circular arrangements clockwise/anticlockwise direction matters, and left/right reverses when facing the centre versus facing outward.

Percentage change = (new - old)/old x 100; successive percentage changes of a% and b% give a net change of a + b + ab/100 percent.

Profit and loss: Profit% = (SP - CP)/CP x 100; Loss% = (CP - SP)/CP x 100; when two articles are sold at the same price with equal profit% and loss%, the seller always incurs a net loss of (x/10)^2 percent.

Simple interest SI = P x R x T/100; compound interest amount A = P(1 + R/100)^T, and CI = A - P. For 2 years, CI - SI = P(R/100)^2.

Speed, time, distance: Distance = Speed x Time. To convert km/h to m/s multiply by 5/18; to convert m/s to km/h multiply by 18/5.

Average = sum of observations / number of observations; if every value is increased by k, the average increases by k, and if multiplied by k, the average is multiplied by k.

Ratio and proportion: if a:b = c:d then ad = bc. To divide a sum in ratio a:b:c, the shares are total x a/(a+b+c), and so on.

Time and work: if A finishes in x days and B in y days, together they take xy/(x+y) days; work rate adds, so 1/x + 1/y = 1/together.

Mensuration: area of circle = pi r^2, circumference = 2 pi r; area of triangle = 1/2 x base x height; volume of cylinder = pi r^2 h; volume of sphere = 4/3 pi r^3.

Number system: HCF x LCM = product of the two numbers; a number is divisible by 3 if its digit sum is divisible by 3, by 9 if the digit sum is divisible by 9, and by 11 if the alternating digit-sum difference is 0 or a multiple of 11.

Subject-verb agreement: a singular subject takes a singular verb; with 'either...or' and 'neither...nor' the verb agrees with the nearer subject; 'each', 'every', 'everyone' and 'nobody' take singular verbs.

Articles: 'a' before consonant sounds and 'an' before vowel sounds (an hour, a university); 'the' is used for unique things, superlatives and previously mentioned nouns.

Tenses: present perfect (has/have + past participle) is used for past actions with present relevance; past perfect (had + past participle) marks the earlier of two past actions.

Prepositions: 'since' with a point of time and 'for' with a duration; 'between' for two and 'among' for more than two; 'on' for days and dates, 'in' for months, years and seasons, 'at' for exact times.

Active to passive: move the object to the subject position, use the correct form of 'be' plus the past participle, and add 'by' with the agent. Example: 'She writes a letter' becomes 'A letter is written by her.'

Direct to indirect speech: change the reporting verb to 'said that', shift the tense one step back, and change pronouns and time words (now becomes then, today becomes that day, tomorrow becomes the next day).

Common confusions: 'affect' is a verb and 'effect' a noun; 'principal' means chief or head and 'principle' means a rule; 'its' is possessive and 'it's' means 'it is'.

Vocabulary building: synonyms and antonyms are tested alongside one-word substitutions (for example, 'one who knows everything' = omniscient) and idioms such as 'to let the cat out of the bag' meaning to reveal a secret.

Comprehension strategy: read the passage once for the main idea, then locate the specific sentence that supports each answer; eliminate options that are true in general but not stated in the passage.

वर्णमाला में स्वर 11 और व्यंजन 33 माने जाते हैं; स्वर के तीन भेद हैं- ह्रस्व, दीर्घ और प्लुत, तथा व्यंजन के भेद स्पर्श, अंतःस्थ और ऊष्म होते हैं।

संधि के तीन प्रकार हैं- स्वर संधि, व्यंजन संधि और विसर्ग संधि। उदाहरण: विद्या + आलय = विद्यालय (दीर्घ संधि), नर + इंद्र = नरेंद्र (गुण संधि)।

समास के मुख्य भेद: तत्पुरुष, कर्मधारय, द्विगु, द्वंद्व, बहुव्रीहि और अव्ययीभाव। 'राजपुत्र' तत्पुरुष है, 'नीलकमल' कर्मधारय और 'चौराहा' द्विगु समास है।

उपसर्ग शब्द के आरम्भ में जुड़कर अर्थ बदलते हैं (अनु + शासन = अनुशासन), जबकि प्रत्यय शब्द के अंत में जुड़ते हैं (लड़क + पन = लड़कपन)।

संज्ञा के पाँच भेद हैं- व्यक्तिवाचक, जातिवाचक, भाववाचक, समूहवाचक और द्रव्यवाचक; सर्वनाम के भेद पुरुषवाचक, निजवाचक, निश्चयवाचक, अनिश्चयवाचक, प्रश्नवाचक और संबंधवाचक हैं।

क्रिया के भेद: सकर्मक और अकर्मक; काल के तीन भेद- वर्तमान, भूत और भविष्यत्। वाच्य तीन प्रकार के होते हैं- कर्तृवाच्य, कर्मवाच्य और भाववाच्य।

अलंकार: अनुप्रास में एक ही वर्ण की आवृत्ति होती है, उपमा में 'सा', 'जैसा' आदि वाचक शब्द आते हैं, रूपक में उपमेय और उपमान में अभेद दिखाया जाता है।

मुहावरे अर्थ सहित: 'आँख का तारा' = बहुत प्यारा, 'नाक में दम करना' = परेशान करना, 'लोहे के चने चबाना' = कठिन कार्य करना, 'अंधे की लाठी' = एकमात्र सहारा।

वर्तनी और शब्द-शुद्धि पर ध्यान दें: 'पूर्ण' सही है 'पुर्ण' नहीं, 'आशीर्वाद' सही है 'आशिर्वाद' नहीं; तत्सम शब्द संस्कृत से सीधे आए हैं और तद्भव शब्द उनके बदले हुए रूप हैं, जैसे दुग्ध से दूध।

Keyboard shortcuts: Ctrl+C copy, Ctrl+X cut, Ctrl+V paste, Ctrl+Z undo, Ctrl+Y redo, Ctrl+A select all, Ctrl+S save, Ctrl+P print, Ctrl+F find, Alt+F4 close the active window.

MS Word: Ctrl+B bold, Ctrl+I italic, Ctrl+U underline; F7 opens spelling and grammar check; Ctrl+Enter inserts a page break; the default file extension for Word 2007 and later is .docx.

MS Excel: a cell reference such as B4 means column B, row 4; the formula bar begins with '='; SUM, AVERAGE, COUNT, MAX and MIN are common functions; F2 edits the active cell.

Computer fundamentals: the CPU is the brain of the computer and has the ALU and control unit; RAM is volatile primary memory, ROM is non-volatile, and 1 KB = 1024 bytes, 1 MB = 1024 KB, 1 GB = 1024 MB.

Input devices include keyboard, mouse, scanner and microphone; output devices include monitor, printer and speaker; both input and output devices include touchscreen and modem.

Internet basics: HTTP/HTTPS are web protocols, an IP address identifies a device on a network, a URL is a web address, and a search engine such as Google indexes web pages rather than hosting them.

Typing skill: touch typing uses the home row (A S D F for the left hand and J K L ; for the right hand) with the index fingers on F and J, which carry raised bumps for positioning without looking.

Typing speed is measured in words per minute (WPM); gross speed = total words typed / minutes, and net speed subtracts errors. Accuracy is calculated as (correct characters / total characters) x 100.

File and system basics: Ctrl+Shift+Esc opens Task Manager, Alt+Tab switches between open applications, Ctrl+Alt+Delete opens the security screen, and a file extension such as .txt or .pdf tells the system which program opens the file.