(a) a balloon is filled with helium (he) at an absolute pressure of 1.80 atm, a temperature of 25.0 °c, and it occupies a volume of 3.00 m^3. the balloon rises in the atmosphere to a height where the pressure is 0.500 atm and the temperature is -20 °c. 1) find the final volume of the balloon. 2) calculate the number of moles of the gas 3) calculate the internal energy of the helium gas in the balloon at the final altitude. (b) in a certain process, the temperature rises from 0.00 °c to 90 °c as 900 j of heat are extracted from 5 moles of an ideal gas. find the work done by the gas in this process. (r = 8.314 j/mk)

Which simple machine is not part of this compound machine? a. lever b. pulley c. inclined plane d. wheel and axle

4r-134a enters the condenser of a residential heat pump at 800 kpa and 50°c at a rate of 0.022 kg/s and leaves at 750 kpa subcooled by 3°c. the refrigerant enters the compressor at 200 kpa superheated by 4°c determine (a) the isentropic efficiency of the compressor, (b) the rate of heat supplied to the heated room, and (c) the cop of the heat pump. also, determine (d) the cop and rate of heat supplied to the heated room if this heat pump operated on the ideal vapor-compression cycle between the pressure limits of 200 and 800 kpa. (0.757, 4.37 kw, 5.12, 6.18, 3.91 kw)

Use the library or internet to research each planet. make a chart comparing the following: approximate surface temperature relative surface gravity compared to earth atmospheric gases water in any form: solid, gas, or liquid when you have completed your chart, use the information you have collected to answer the following questions: which is the hottest planet? which is the coldest planet? which planet's temperature is closest to that of earth? (note: water boils at 100°c/212°f. water freezes at 0°c/32°f) which planet has the greatest gravitational attraction? which planet has the least gravitational attraction? which planet's gravitational pull is closest to that of earth? do any of the planets have oxygen in their atmosphere? which planet's atmosphere most resembles that of earth? do any of the planets have flowing water? which planet's water resources (solid, gas, or liquid) might be close to the amount on earth? which planet most resembles earth in terms of all of the factors: temperature, gravity, atmosphere, and water? if earth became an uninhabitable planet, which planet do you think would be the next best to live on? explain your answer.