Barometer is taken from the base to the top of a 279-m tower. assuming the density of air is 1.29 kg/m3, what is the measured change in pressure?

Answer : P = 3527 Pa Explanation: Given : height, h = 279 m and density of air , Ď = 1.29 kg/m3 Change in pressure , P = h*Ď*g We know that gravity, g = 9.8 m/s2 Therefore P = 279 * 1.29 * 9.8 = 3527 Pa

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j