Jharkhand Police Constable cheat sheet

Jharkhand was carved out of Bihar on 15 November 2000 as India's 28th state, with Ranchi as its capital; the day is observed as Jharkhand Formation Day.

The President of India is elected by an electoral college of elected MPs and elected MLAs; the Election Commission of India (Article 324) conducts Lok Sabha, Rajya Sabha, and state assembly elections.

The Tropic of Cancer passes through eight Indian states: Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura, and Mizoram.

National sports awards: Major Dhyan Chand Khel Ratna (highest), Arjuna Award, Dronacharya Award (coaches), and Dhyan Chand Award (lifetime achievement).

Jharkhand's state animal is the elephant, state bird is the koel, state tree is the sal, and state flower is the palash (flame of the forest).

The Reserve Bank of India was established on 1 April 1935 and nationalised in 1949; it issues currency and sets the repo rate through the Monetary Policy Committee.

Indian Space Research Organisation (ISRO) is headquartered in Bengaluru; Chandrayaan-3 achieved a soft landing near the lunar south pole in August 2023.

The G20 summit hosted by India in 2023 was held in New Delhi under the theme 'Vasudhaiva Kutumbakam' (One Earth, One Family, One Future).

The Nobel Prize is awarded in six categories; the Economics prize was added in 1968 and is funded by Sveriges Riksbank, not by Alfred Nobel's will.

Newton's second law: F = ma; SI unit of force is the newton (N), where 1 N = 1 kg·m/s². Weight = mass × g, with g ≈ 9.8 m/s² on Earth.

Ohm's law: V = IR. In a series circuit, current is the same through each resistor and total resistance is the sum; in parallel, voltage is the same and 1/R = 1/R1 + 1/R2.

pH scale runs 0–14: pH < 7 is acidic, pH = 7 neutral, pH > 7 basic. Litmus turns red in acid and blue in base; phenolphthalein is colourless in acid and pink in base.

Photosynthesis: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂, occurring in chloroplasts with chlorophyll; oxygen is released from water, not carbon dioxide.

Human blood has 4 main groups (A, B, AB, O); O negative is the universal donor and AB positive the universal recipient. Normal adult haemoglobin is about 12–17 g/dL.

Mitochondria are the site of aerobic respiration and ATP production; ribosomes synthesise protein; the nucleus contains DNA; lysosomes are the cell's digestive bodies.

The three laws of motion: inertia (first), F = ma (second), and equal and opposite reaction (third). Momentum p = mv is conserved in the absence of external force.

Sound travels fastest in solids, slower in liquids, slowest in gases; it cannot travel through a vacuum. Light travels at about 3 × 10⁸ m/s in vacuum.

Blood pressure is measured with a sphygmomanometer; normal adult value is about 120/80 mm Hg, where the higher figure is systolic pressure.

Average = sum of values ÷ number of values; if a person of weight w joins a group of n people with average A, new average = (nA + w)/(n + 1).

Profit percentage = (SP − CP)/CP × 100; loss percentage = (CP − SP)/CP × 100. Successive discounts of a% and b% equal a + b − ab/100.

Simple interest SI = P × R × T/100; compound interest CI = P(1 + R/100)^T − P. For 2 years, CI − SI = P(R/100)².

Speed = distance ÷ time. To convert km/h to m/s multiply by 5/18; to convert m/s to km/h multiply by 18/5.

Work: if A alone takes x days and B alone takes y days, together they take xy/(x + y) days.

Train crossing a pole takes time = length of train ÷ speed; crossing a platform of length L takes (train length + L) ÷ speed.

Area formulas: rectangle l × b; triangle ½ × base × height; circle πr²; trapezium ½(a + b)h; volume of cylinder πr²h; sphere (4/3)πr³.

Ratio and mixture: alligation rule gives ratio of quantities as (mean price − cheaper price) : (dearer price − mean price).

Percentage change in area of a rectangle when length changes by x% and breadth by y% is x + y + xy/100 percent.

Alphabet positions: A = 1 … Z = 26. Opposite-letter pairs sum to 27 (A–Z, B–Y, C–X), useful for coding-decoding questions.

In a series with a constant difference, the nth term is a + (n − 1)d and the sum is n/2 × (first + last).

Blood relations: draw a family tree using symbols; vertical lines for generations, horizontal for siblings/spouse, and never assume gender from a name.

Direction sense: track net displacement with a coordinate sketch; north = +y, east = +x, and use Pythagoras for shortest distance.

Syllogism: a conclusion follows only if it is true in every possible Venn diagram of the premises; 'some' and 'no' statements are reversible in specific ways.

Clock problems: the minute hand gains 5.5° per minute on the hour hand; hands coincide every 65 5/11 minutes.

Calendar: a normal year shifts the day of the week by 1, a leap year by 2. A century has 5 odd days (100 years = 24 leap + 76 ordinary).

Coding-decoding: check for letter-shift (+1, −2), reversal, or position-sum patterns before assuming a substitution cipher.

Seating arrangement: fix the most constrained person first, then place others relative to that anchor; for circular arrangements facing centre, left is clockwise.

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.

Directive Principles of State Policy are in Part IV (Articles 36–51) and are non-justiciable; Fundamental Duties were added by the 42nd Amendment (1976) in Article 51A.

The Indian Constitution was adopted on 26 November 1949 and came into force on 26 January 1950; it originally had 395 Articles, 22 Parts, and 8 Schedules.

The Indian National Congress was founded in 1885 by A. O. Hume; the partition of Bengal in 1905 triggered the Swadeshi Movement.

The Himalayan rivers are perennial (Indus, Ganga, Brahmaputra); peninsular rivers such as the Godavari and Krishna are rain-fed and seasonal.

The monsoon retreats from the northwest around September; the southwest monsoon (June–September) provides about 75% of India's annual rainfall.

GDP at market prices = C + I + G + (X − M). Inflation is measured in India by the Consumer Price Index (CPI) and Wholesale Price Index (WPI).

The Constitution's Eighth Schedule lists 22 scheduled languages; Hindi in Devanagari script is the official language of the Union under Article 343.

The Mauryan Empire under Ashoka (268–232 BCE) promoted dhamma; the Gupta period is called the Golden Age of Indian art and literature.

Jharkhand has 24 districts and 5 divisions; it borders Bihar to the north, West Bengal to the east, Odisha to the south, and Chhattisgarh and Uttar Pradesh to the west.

The Chota Nagpur Plateau covers most of Jharkhand and is rich in minerals; Jharkhand produces a large share of India's coal, iron ore, mica, and copper.

The Damodar, Subarnarekha, North Koel, South Koel, Barakar, and Kharkai are the main rivers; the Damodar Valley Corporation was India's first multipurpose river valley project (1948).

Birsa Munda (1875–1900) led the Ulgulan (Mulki) rebellion against British rule and is revered as 'Dharti Aba'; his birth anniversary, 15 November, is Janjatiya Gaurav Divas.

The Santhal Hul of 1855–56 was led by Sidhu and Kanhu Murmu against zamindars and the British; the Tana Bhagat movement was led by Jatra Bhagat.

Jharkhand's legislature has 81 assembly seats and 14 Lok Sabha seats; the state was formed after the Bihar Reorganisation Act, 2000.

Major festivals include Karma, Sohrai, Sarhul, Tusu, and Bandna; Sohrai painting of Hazaribagh is a GI-tagged tribal wall-art tradition.

Jamshedpur hosts Tata Steel, India's first private steel plant (established 1907); Bokaro Steel Plant and the Sindri fertiliser plant are other key industrial units.

Betla National Park in Latehar district was among India's first tiger reserves; Dalma Wildlife Sanctuary near Jamshedpur is known for elephants.

Hindi noun gender: most words ending in 'aa' (आ) are masculine (लड़का, घोड़ा) and most ending in 'ii' (ई) are feminine (लड़की, नदी), with exceptions such as पानी (masculine).

Hindi cases are shown by postpositions: ने (ergative, with perfective transitive verbs), को (accusative/dative), से (ablative/instrumental), में (locative), का/के/की (genitive agreeing with the possessed noun).

Sandhi: स्वर संधि (vowel junction), व्यंजन संधि (consonant junction), and विसर्ग संधि; e.g., सूर्य + उदय = सूर्योदय (गुण संधि).

Common Hindi idioms: 'नौ दो ग्यारह होना' = to run away; 'आँख का तारा' = very dear; 'ईद का चाँद' = something seen rarely.

English tenses: present perfect (has/have + past participle) for past actions with present relevance; past perfect (had + participle) for the earlier of two past actions.

Active to passive: object becomes subject, verb becomes be + past participle, agent follows 'by'; only transitive verbs can be made passive.

Articles: 'a/an' for indefinite countable singulars (an before vowel sounds), 'the' for definite or unique references and superlatives.

Direct to indirect speech: present tense in the reporting verb usually shifts the reported verb one step back (present → past, will → would); time words change (now → then, today → that day).

Subject-verb agreement: each/every/either/neither takes a singular verb; 'neither … nor' and 'either … or' agree with the nearer subject.