Terrestiral palnts take up huge amount of water but very less is evaporated from the leaves in transpiration.

There are two separate coils in a heater . If one col is used then it takes 20 minutes to boil a given amount of water completely. But when its other coil is used then it takes 5 minutes to boil the same amount of water. Calculate the time taken to boil the same amount of water using the same source when the two coils are connected (1) in series and (2) in parallel.

Two tanks A and B contain water at 30^@C and 80^@C respectively calculate the amount of water that must be taken from each tank respectively to prepare 40 kg of water at 50^@C

A heating coil can heat the water of a vessel from 20^(@)C to 60^(@)C in 30 minutes . Two such heating coils are put in series and then used to heat the same amount of water through the same temperature range. The time taken now will be (neglecting thermal capacity of the coils)

Two rectangular blocks, having identical dimensions, an be arranged either in configuration-I or in configuration-II as shown in the figure. One of the blocks has thermal conductivity k and the other 2k. The temperature difference between the ends along the x-axis is the same in both the configurations. It takes 9s to transport a certain amount of heat from the hot end to the cold end in the configuration-I. The time to transport the same amount of heat in the configuration-II is