(A) The pressure at 10 m below the surface of the ocean is about 2.00×10^5 Pa. Which of the following statements is true? a) The weight of a column of seawater 1 m^2 in cross-section and 10 m high is about 2.00×10^5 N. b) The weight of a column of seawater 1 m^2 in cross-section and 10 m high plus the weight of a column of air with the same cross-section extending up to the top of the atmosphere is about 2.00×10^5 N. c) The weight of 1 m3 of seawater at 10 m below the surface of the ocean is about 2.00×10^5 N. d) The density of seawater is about 2.00×10^5 times the density of air at sea level. (B) Now consider the pressure 20 below the surface of the ocean. Which of the following statements is true? a) The pressure is twice that at a depth of 10 m. b) The pressure is the same as that at a depth of 10 m. c) The pressure is equal to that at a depth of 10 m plus the weight per 1 m^2 cross-sectional area of a column of seawater 10 m high. d) The pressure is equal to the weight per 1 m^2 cross-sectional area of a column of seawater 20 m high.

Aball tossed vertically upward from the ground next to a building passes the bottom of a window 1.8 s after being tossed and passes the top of the window 0.20 s later. the window is 2.0 m high from top to bottom. what was the ball's initial velocity? the unit vector j^ is directed upward. how far is the bottom of the window from the launch position? how high does the ball rise above the launch position?

An internally reversible refrigerator has a modified coefficient of performance accounting for realistic heat transfer processes of where qin is the refrigerator cooling rate, qout is the heat rejection rate, and is the power input. show that copm can be expressed in terms of the reservoir temperatures tc and th, the cold and hot thermal resistances rt,c and rt,h, and qin, as where rtot rt,c rt,h. also, show that the power input may be expressed as 1.39 a household refrigerator operates with cold- and hot-temperature reservoirs of tc 5 c and th 25 c, respectively. when new, the cold and hot side resistances are rc,n 0.05 k/w and rh,n 0.04 k/w, respectively. over time, dust accumulates on the refrigerator’s condenser coil, which is located behind the refrigerator, increasing the hot side resistance to rh,d 0.1 k/w. it is desired to have a refrigerator cooling rate of qin 750 w. using the results of problem 1.38, determine the modified coefficient of performance and the required power input w under (a) clean and (b) dusty coil conditions. internally reversible refrigerator qout qin w high-temperature reservoir low-temperature reservoir th th,i tc,i tc high-temperature side resistance low-temperature side resistance w qin th tc qinrtot tc qinrtot copm tc qinrtot th tc

Unpolarized light of intensity so passes through two sheets of polarizing material whose transmission axes make an angle of 60∘ with each other as shown in the figure. what is the intensity of the transmitted beam, st?