Physics, 29.01.2020 18:48 ShawnaLove4808
An archer pulls back the string of a bow to release an arrow at a target. which kind of potential energy is transformed to cause the motion of the arrow?
a. chemical
b. gravitational
c. elastic
d. magnetic
Answers: 2
Physics, 22.06.2019 02:30
Awave travels at a speed of 5.2 m/s. if the distance between crests is 0.40 m, what is the frequency of the wave? use f=v/wavelength a. 13 hz b. 2.1 hz c. 0.077 hz d. 5.6 hz
Answers: 1
Physics, 22.06.2019 03:30
As part of an industrial process, air as an ideal gas at 10 bar, 400k expands at steady state through a valve to a pressure of 4 bar. the mass flow rate of air is 0.5 kg/s. the air then passes through a heat exchanger where it is cooled to a temperature of 295k with negligible change in pressure. the valve can be modeled as a throttling process, and kinetic and potential energy effects can be neglected. (a) for a control volume enclosing the valve and heat exchanger and enough of the local surroundings that the heat transfer occurs at the ambient temperature of 295 k, determine the rate of entropy production, in kw/k. (b) if the expansion valve were replaced by an adiabatic turbine operating isentropically, what would be the entropy production? compare the results of parts (a) and (b) and discuss.
Answers: 3
Physics, 22.06.2019 10:20
Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i.e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.
Answers: 2
An archer pulls back the string of a bow to release an arrow at a target. which kind of potential en...
History, 26.03.2020 01:54
Social Studies, 26.03.2020 01:54
History, 26.03.2020 01:54
Mathematics, 26.03.2020 01:54
History, 26.03.2020 01:54
Mathematics, 26.03.2020 01:54
Biology, 26.03.2020 01:54
Mathematics, 26.03.2020 01:54
Mathematics, 26.03.2020 01:54