According to the law of conservation of energy,
a) an object loses most of its energy as friction.
b) the total amount of energy for a system stays the same.
c) the potential energy of an object is always greater than its kinetic energy.
d) the kinetic energy of an object is always greater than its potential energy.

Write the equation for momentum, first using symbols for the variables, then using words for the variables.

Asilver dollar is dropped from the top of a building that is 1324 feet tall. use the position function below for free-falling objects. s(t) = −16t2 + v0t + s0 (a) determine the position and velocity functions for the coin. s(t) = v(t) = (b) determine the average velocity on the interval [1, 2]. ft/s (c) find the instantaneous velocities when t = 1 second and t = 2 seconds. v(1) = ft/s v(2) = ft/s (d) find the time required for the coin to reach the ground level. (round your answer to three decimal places.) t = s (e) find the velocity of the coin at impact. (round your answer to three decimal places.) ft/s

By what primary heat transfer mechanism does the sun warm the earth?