Speed of a boat in still water is three times the speed of the boat in upstream. If the boat takes 20 minutes to cover 15 km in downstream, then find the speed of the boat in still water.
Let speed of the boat in still water be ‘3x’ km/h. Speed of the boat in upstream = 3x ÷ 3 = ‘x’ km/h Speed of the stream = 3x – x = ‘2x’ km/h Speed of the boat in downstream = 3x + 2x = ‘5x’ km/h ATQ; (15/20) × 60 = 45 So, 5x = 45 Or, x = 9 So, speed of the boat in still water = 3 × 9 = 27 km/h
Reclammation of acidic soils is done by the use of……………………..
Biological oxidation of elemental Sulphur is carried out by which of the following bacteria?
Which property of soil usually reflects the extent of leaching and weathering of soils?
The soils of grassland ecosystems, characterized by a thick, dark surface horizon comes under which soil order?
Which organic component, constituting approximately 10-30% in plant tissues, is often categorized as "very slowly decomposed"?
In soil, heat transfer is mainly due to
What is the term used for the study of soil in relation to higher plants?
Choose the best answer from the following options
What term is used to describe the process when the parent material is moved or transported primarily by the force of gravity?
The absolute density of soil is also referred to as ……………….which is generally 2.60-2.75 gm/cm3
What is the primary function of humus in soil?