A 35 lb object is subjected to an applied upward force of 20 lbf. The only other force acting on the object is the force of gravity. The acceleration of gravity is 32.2 ft/s². Determine the weight of the object, in lbf, and the net acceleration of the object, in ft/s².

Which of the following principles is the closest interpretation of the first law of thermodynamics? O Energy is continuously and indefinitely discharged more than it receives. O The mass within a closed control volume does not change. O The change of the total energy is equal to the rate if work performed. ON O All real processes tend toward increased entropy. O The net energy crossing the system boundary is the change in energy inside the system.

INTRODUCTION: In thermodynamics, energy can be neither created nor destroyed (1st law): it is either converted to usable work or lost as waste heat. The second law of thermodynamics states that the total entropy (disorder) of a system will never decrease over time; that is, systems can only be at constant entropy or have increasing entropy. This may be restated by saying that there is an upper limit to the efficiency of the conversion of heat to work, as in a heat engine. From these principles of thermodynamics, it is clear that there is an upper limit to how efficient power generation can be at most power plants. Many power plants, including those fueled by fossil fuels, nuclear sources, geothermal sources, biomass, and solar thermal, operate by generating a source of heat (burning fossil fuels, reacting nuclear materials, using the sun’s rays, etc.), using this heat source to heat water to steam, and passing this steam through a turbine. When the turbine spins, power is generated.…

An internal combustion engine is a commonly-analyzed thermodynamic system. In a few sentences, describe the flows of energy and matter across the boundaries of a typical engine.