Plants transpire more rapidly in the light than in the dark. This is largely because light stimulates the opening of the stomata (mechanism). Light also speeds up transpiration by warming the leaf. Plants transpire more rapidly at higher temperatures because water evaporates more rapidly. As the temperature increases, transpiration will increase due to a higher concentration in sunlight and warm air. However, if temperatures remain high for long periods of time eventually leading to drought, transpiration may go down to conserve water in the plant.
An electromagnet is a kind of magnet whose magnetic field is created by flow of electric current. The magnetic field disappears when the current stops.
The greatest advantage of an electromagnet over a permanent magnet is that it has the advantage of controlled holding power and on - command release.
Through the application of controlled DC electric current, electromagnets have the ability to attract and hold ferrous materials with varying degrees of force and to release the item as required.
When clouds get so full of water droplets that they can not hold any more, the water falls back to the ground as rain but sometimes water droplets freeze and fall to the ground as snow, sleet, or hail.
