Water is supplied to the atmosphere by evaporation from the surface, and leaves the atmosphere via precipitation. the average amount of time a water molecule spends in the atmosphere can be derived by dividing the amount of water vapor in the atmosphere (1.1x1016 by the globally-averaged rate of precipitation to the earth’s surface of 3.1 mm −1 . using these data, calculate how many days, on average, a water molecule spend in the atmosphere before it precipitates out.

What is created when solids,liquids,an gases mix with one another

How is the gravitational force related to the distance between two objects?

Search coils and credit cards. one practical way to measure magnetic field strength uses a small, closely wound coil called a search coil. the coil is initially held with its plane perpendicular to a magnetic field. the coil is then either quickly rotated a quarter-turn about a diameter or quickly pulled out of the field. (a) derive the equation relating the total charge q that flows through a search coil to the magnetic-field magnitude b. the search coil has n turns, each with area a, and the flux through the coil is decreased from its initial maximum value to zero in a time ∆t. the resistance of the coil is r, and the total charge is q = i∆t, where i is the average current induced by the change in flux. (b) in a credit card reader, the magnetic strip on the back of a credit card is rapidly “swiped” past a coil within the reader. explain, using the same ideas that underlie the operation of a search coil, how the reader can decode the information stored in the pattern of magnetization on the strip. (c) is it necessary that the credit card be “swiped” through the reader at exactly the right speed? why or why not?