(a) Sand dunes on a desert island move as sand is swept up the windward side to settle in the leeward side. Such "walking" dunes have been known to travel 24 feet in a year and can travel as much as 105 feet per year in particularly windy times. Calculate the average speed in each case in m/s.

(b) Fingernails grow at the rate of drifting continents, about 10mm/yr. Approximately how long did it take for North America to separate from Europe, a distance of about 3540 miles?
Note I would also like to see the problems solved as opposed to only the answers. Thanks a bunch.

Originally Posted by Monet
(a) Sand dunes on a desert island move as sand is swept up the windward side to settle in the leeward side. Such "walking" dunes have been known to travel 24 feet in a year and can travel as much as 105 feet per year in particularly windy times. Calculate the average speed in each case in m/s.

(b) Fingernails grow at the rate of drifting continents, about 10mm/yr. Approximately how long did it take for North America to separate from Europe, a distance of about 3540 miles?
Note I would also like to see the problems solved as opposed to only the answers. Thanks a bunch.
(a) $\displaystyle avg \, speed = \frac{total \, distance}{total \, time}$

to start, you need to convert ft to meters and a year to seconds

(b) $\displaystyle total \, time = \frac{total \, distance}{avg \, speed}$

you'll need to convert 3540 miles to millimeters

in future, post physics topics in the math topics forum