Question
A boat takes 7 hours to cover 252 km upstream and 9
hours to cover 450 km downstream. Find the time taken by the boat to cover 546 km upstream and 572 km downstream if speed of boat in still water is increased by 4 km/h and speed of stream is decreased by 2 km/h.Solution
Upstream speed = 252/7 = 36 km/h Downstream speed = 450/9 = 50 km/h Speed of boat in still water = (36 + 50)/2 = 43 km/h  Speed of stream = (50 – 36)/2 = 7 km/h Increased speed of boat in still water = 43 + 4 = 47 km/h Decreased speed of stream = 7 – 2 = 5 km/h Required time taken = 546/(47 – 5) + 572/(47 + 5) = 13 + 11 = 24 hours
The Indian council of Agricultural Research (ICAR) set up an All India Soil Survey Committee in 1953 which divided the Indian soils into …….. major ...
Which clay mineral group is known for its ability to swell and expand when wetted?
The addition of which substance is LEAST likely to result in immediate nitrogen loss from the soil?
Match the following:
1.        Soil moisture tension                                          ...
Flooding is the method used for the reclamation practice in which of the problematic soil?
Soil is a natural body composed of mineral and organic costituents, having definite genesis and a distinct nature of its own. Who amongst the following ...
 The root nodule of legumes contain a pink pigment which has affinity for oxygen is
Which class of seed is exempted from certification?
In which soil order is cryopedoturbation, a frost churning process resulting from the freezing and thawing of soil material, predominantly observed?
Example of igneous rock is