A boy of mass 60 kg jumps off a truck of mass 140kg travelling at 7.7m/s. If he runs towards the truck with velocity of 2.5m/s calculate the momentum of the boy on jumping off the truck and the loss of kinetic energy the moment the boy jumped off

Which of the following changes to a pipe would increase the conductance by a factor of 12? 1.quadrupling the length and tripling the radius.2.reducing the length by a factor of and doubling the radius.3.tripling the length and reducing the radius by a factor of .4.reducing the length but a factor of and doubling the radius.

In the united states, tornadoes generally occur because of the freezing of ocean water underwater earthquakes meeting of cool and warm air masses shifting of warm and cool ocean currents

Scientist have use computer models to create a series of maps that show how susceptible coastal cities in island countries are to the sea rising at different levels.the map shows that a 1 meter rise would swap cities all along the us eastern seaboard. a 6-meter sea level rise with sub merge a large part of florida. thermal expansion has already raise the oceans 10 to 20 centimeters the most likely cause,directly and indirectly, for such a rise in sea level is