BD Police ASI Written flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

মাত্রাহীন বর্ণ

বাংলা বর্ণমালায় যে বর্ণগুলোর উপরে মাত্রা নেই। স্বরবর্ণ 'অ' ও 'আ' মাত্রাহীন; এছাড়া 'এ' ও 'ঐ'-এরও মাত্রা নেই বলে অনেকের মতে এরা মাত্রাহীন।

চর্যাপদ

বাংলা ভাষার আদি নিদর্শন, বৌদ্ধ সহজিয়া সিদ্ধাচার্যদের রচিত পদসংকলন। হরপ্রসাদ শাস্ত্রী ১৯০৭ সালে নেপালের রাজদরবারে এর পুঁথি আবিষ্কার করেন।

অমিত্রাক্ষর ছন্দ

যে ছন্দে প্রতি চরণের শেষে মিল থাকে না, কিন্তু অন্ত্যমিলবিহীন ভাবপ্রবাহ থাকে। মাইকেল মধুসূদন দত্ত বাংলা সাহিত্যে এ ছন্দের প্রবর্তক।

Gerund

A verb form ending in -ing that acts as a noun in a sentence, such as 'Reading is fun' or 'He enjoys swimming'. It can serve as subject, object or complement.

Passive voice formation

The object of an active sentence becomes the subject, and the verb becomes a form of 'be' plus the past participle. Example: 'The letter was written by Rahim.'

Blank verse

Unrhymed poetry written in iambic pentameter, with five stressed and five unstressed syllables per line. Milton used it in 'Paradise Lost' and Shakespeare in his plays.

Compound interest formula

A = P(1 + r/100)^t, where P is principal, r is the annual rate percent and t is time in years. The interest earned equals A minus P.

Average speed, equal distances

When two equal distances are covered at speeds a and b, average speed is 2ab ÷ (a + b). It is less than the simple mean of a and b.

LCM and HCF relation

For any two positive integers, the product of their LCM and HCF equals the product of the numbers. This lets you find one value when the other three are known.

Combined work formula

If A alone completes a job in x days and B in y days, working together they finish it in xy ÷ (x + y) days, assuming constant independent rates.

Bangladesh Constitution adoption

The Constitution of Bangladesh was adopted on 4 November 1972 and took effect on 16 December 1972. It originally contained 153 articles arranged in 11 parts.

UN Security Council

The UN organ with 15 members: five permanent members holding veto power (China, France, Russia, UK, USA) and ten members elected for two-year terms.

SAARC

The South Asian Association for Regional Cooperation, founded in 1985, with eight member states and its secretariat headquartered in Kathmandu, Nepal.

Bangladesh national symbols

National flower is the water lily (shapla), national fruit jackfruit, national bird the oriental magpie-robin (doyel), and national animal the Bengal tiger.

RAM versus ROM

RAM is volatile working memory that loses its contents when power is removed. ROM is non-volatile, retains data permanently, and typically stores firmware such as the BIOS.

Byte conversion

One byte equals eight bits. One kilobyte is 1024 bytes, one megabyte is 1024 kilobytes, and one gigabyte is 1024 megabytes in binary measurement.

Worm versus virus

A virus attaches to host files and needs them to spread, while a worm self-replicates and spreads across networks without attaching to other files.

IPv4 address size

An IPv4 address is 32 bits long, written as four decimal octets each ranging from 0 to 255, such as 192.168.0.1. IPv6 uses 128 bits.

Newton's second law

The net force on an object equals its mass multiplied by its acceleration, F = ma. Force is measured in newtons, where 1 N = 1 kg·m/s².

Ohm's law

Current through a conductor is directly proportional to voltage and inversely proportional to resistance, written V = IR, where V is volts, I amperes and R ohms.

pH scale

A scale from 0 to 14 measuring hydrogen ion concentration, defined as pH = −log₁₀[H⁺]. Values below 7 are acidic, 7 neutral and above 7 basic.

Isotopes

Atoms of the same element with the same number of protons but different numbers of neutrons, giving different mass numbers. Example: carbon-12 and carbon-14.

Photosynthesis equation

Plants convert carbon dioxide and water into glucose and oxygen using sunlight and chlorophyll: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂. It occurs in chloroplasts.

Tropic of Cancer

The latitude line at 23.5° north of the equator, marking the northernmost point where the Sun can appear directly overhead, at the June solstice.

Earth's rotation and revolution

Rotation is the spin on Earth's axis taking about 24 hours and causing day and night. Revolution is the orbit around the Sun taking 365.25 days and causing seasons.

Atmospheric layers

From the surface outward: troposphere, where weather occurs; stratosphere, containing the ozone layer; mesosphere; thermosphere; and exosphere. Temperature trends alternate between layers.

Bangladesh delta

The Ganges (Padma), Brahmaputra (Jamuna) and Meghna rivers join to form the world's largest delta, covering most of Bangladesh and supporting dense agriculture.

Paris Agreement

A 2015 international treaty under the UNFCCC aiming to keep global warming well below 2°C above pre-industrial levels while pursuing efforts to limit it to 1.5°C.

Montreal Protocol

A 1987 international agreement to phase out ozone-depleting substances such as chlorofluorocarbons, credited with helping the ozone layer recover.

Cyclone signal 10

The highest cyclone warning signal in Bangladesh's system of signals 1 to 10, indicating a severe cyclone with very high winds and dangerous storm surge.

Sendai Framework

A 2015–2030 UN agreement on disaster risk reduction with four priorities, including understanding disaster risk and strengthening disaster governance.

Acid rain formation

Sulphur dioxide and nitrogen oxides from burning fossil fuels react with water vapour in the atmosphere to form sulphuric and nitric acids, which fall as acidic precipitation.