A plank with a box on it at one end is gradually raised about the another end. As the angle of inclination with the horizontal reaches 30 degree the box starts to slip and slides 4m down the plank is 4s. find the coefficient of kinetic and static friction?

Carbon 14 is a naturally occurring stable

You've already seen the value of 9.8 in this lesson. what's this value called? what quantity does it represent?

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