Afreight train rolls along a track with considerable momentum. if it rolls at the same speed but hastwice as much mass, its momentum is
a. zero. b. doubled. c. quadrupled. d. unchanged.

b. doubled

Explanation:

The momentum of an object is given by

where

m is the object's mass

v is its velocity

We see that the momentum is directly proportional to mass. Therefore if the speed of the object is unchanged, but the mass is doubled: m' = 2m, the new momentum will be

so the momentum is doubled.

answer is c

explanation:

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​