KEAM flashcards

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

Angle of repose

The maximum angle of an inclined plane at which a body remains at rest; at this angle the component of weight along the plane equals limiting friction, so tanθ = μs.

Stopping potential

The negative potential applied to stop the fastest photoelectrons. It depends on light frequency, not intensity, and satisfies eV0 = hν − φ.

Markovnikov's rule

When HX adds to an unsymmetrical alkene, hydrogen attaches to the carbon bearing more hydrogens, giving the more stable carbocation intermediate.

Henderson–Hasselbalch equation

pH = pKa + log([conjugate base]/[acid]). It predicts buffer pH and shows maximum buffering capacity when pH equals pKa.

Adiabatic process relation

A process with no heat exchange, described by PV^γ = constant, where γ = Cp/Cv. Work done equals (P1V1 − P2V2)/(γ − 1).

Golden ratio

The proportion φ ≈ 1.618 where the whole is to the larger part as the larger is to the smaller; classically used in facade and plan proportions.

Representative fraction

The ratio of drawing length to actual length, written as 1:n. A scale of 1:50 means one unit on paper represents fifty units in reality.

Isometric scale factor

In isometric projection, true lengths are multiplied by about 0.816 so that the 30° axes foreshorten correctly; isometric drawings often use full lengths instead.

Stair rise-plus-going rule

Comfortable stairs satisfy rise + going ≈ 400–450 mm, typically with a riser of 150–175 mm and a tread of 250–300 mm.

Modular brick dimension

A standard brick of 190×90×90 mm with a 10 mm mortar joint gives a coordinated module of 200×100×100 mm for wall planning.

Cardiac output

Volume of blood pumped per minute, equal to stroke volume times heart rate; roughly 5 litres per minute in a resting adult.

Glomerular filtration rate

Volume of plasma filtered by the kidneys per minute, about 125 mL/min; glucose is fully reabsorbed in the proximal tubule.

Tridosha

In Ayurveda, the three functional humours Vata, Pitta and Kapha, whose balance is considered health and whose imbalance is disease.

Homeopathic potency notation

A label such as 30C means the substance was serially diluted 1:100 thirty times, with succussion at each step.

Universal donor blood group

O negative red cells, which lack A, B and RhD antigens and therefore provoke least reaction in recipients of other groups.

Unani four humours

Dam (blood), balgham (phlegm), safra (yellow bile) and sauda (black bile); their equilibrium defines health in Unani medicine.

Liebig's law of the minimum

Crop yield is governed by the nutrient in shortest supply relative to need, not by the total quantity of nutrients available.

Crop coefficient

The factor Kc multiplying reference evapotranspiration to give crop water use; it varies with crop type and growth stage.

Economic threshold level

The pest population density at which the value of crop loss it would cause equals the cost of control measures.

Rhizobium symbiosis

Bacteria in root nodules of legumes reduce atmospheric nitrogen to ammonia, supplying the plant and enriching soil nitrogen.

C3 versus C4 plants

C4 plants such as maize and sugarcane concentrate CO2 before fixation, giving lower photorespiration and higher water-use efficiency than C3 plants.

Silvicultural system

A planned method of tending and harvesting a forest stand, such as clear felling, shelterwood, selection or coppice, chosen to suit species biology.

Forest rotation

The planned interval between establishing a crop of trees and its final felling, distinct from the shorter felling cycle between harvests.

Site index

A measure of forest productivity based on the dominant tree height reached at a standard reference age; higher values indicate better sites.

Shannon diversity index

H' = −Σ pi ln pi, where pi is the proportion of individuals in species i; larger values indicate greater species diversity.

Rumen fermentation

Microbial breakdown of cellulose in the rumen yields volatile fatty acids, the principal energy source for cattle and other ruminants.

Foot-and-mouth disease

A highly contagious viral disease of cloven-hoofed animals caused by an aphthovirus, producing vesicles in the mouth and on the feet.

Composite fish culture

Pond stocking of surface, column and bottom feeding species together, such as catla, rohu and mrigal, to exploit all food niches.

Dissolved oxygen stress

Most pond fish become stressed when dissolved oxygen falls below about 3 mg/L; aeration and reduced stocking raise oxygen levels.

First-order half-life

For first-order elimination the half-life is 0.693/k, constant regardless of dose, unlike zero-order elimination where it rises with concentration.

Volume of distribution

An apparent volume, Vd = Dose/C0, relating the amount of drug in the body to its plasma concentration; large values suggest tissue uptake.

First-pass metabolism

Drug absorbed from the gut passes through the liver before reaching circulation, lowering oral bioavailability; sublingual and intravenous routes avoid it.