Apiece of spacecraft debris initially at rest falls to the earth's surface from a height above the earth equal to one-half of the earth's radius. find the speed at which the piece of debris hits the surface. neglect air resistance and the gravitational pull of the moon.

Asmall metal bar, whose initial temperature was 10° c, is dropped into a large container of boiling water. how long will it take the bar to reach 70° c if it is known that its temperature increases 2° during the first second? (the boiling temperature for water is 100° c. round your answer to one decimal place.) sec how long will it take the bar to reach 98° c? (round your answer to one decimal place.)

Complete the statement about memory improvement. ( )involves organizing and breaking down information into easier groups to expand capacity. rehearsal is the verbal repetition of information. these techniques are especially important for the improvement of ( ) memory.

For which pair of objects would adding the same a