Simple Machines Problems

discussion summary practice problems Problems practice Write something else. A bucket grain elevator is powered by a 150 kW electric motor. Determine its efficiency if it can lift grain to a height of 60 m at a rate of 900 m3/h. Assume the elevator is lifting wheat with a density of 770 kg/m3. Write something different. Write something completely different. numerical problem

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Simple Machines Practice

discussion summary practice problems Practice practice problem 1 Write something else. solution Answer it. practice problem 2 A bucket grain elevator is powered by a 150 kW electric motor. Determine its efficiency if it can lift grain to a height of 60 m at a rate of 900 m3/h. Assume the elevator is lifting wheat with a density of 770 kg/m3. solution Start with ...

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Simple Machines

discussion summary practice problems Discussion In the most general sense, a machine is any device that can be used to perform a task. In the mechanical sense, a machine is a device for transmitting work from one location to another. A bicycle is a machine. The rider does work on the pedals, which in turn do work on the front crank, which ...

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power physics Problems

discussion summary practice problems power physics Problems practice A typical adult in the United States consumes something like 2000 dietetic calories of food per day. Determine the average power generated by such an adult (assuming he or she is not gaining or losing weight). Determine the cost of operating a 7000 Btu, room-sized air conditioner in New York City for the ...

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power physics Practice

discussion summary practice problems Practice practice problem 1 A typical adult in the United States consumes something like 2000 dietetic calories of food per day. Determine the average power generated by such an adult (assuming he or she is not gaining or losing weight). solution We have to assume here that all the food energy consumed goes into work on ...

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power physics Summary

discussion summary practice problems power physics Summary Definition Power is the rate at which work is done (or the rate at which energy is consumed). non-calculus calculus P = ΔW Δt P = dW dt Where P = power W = work t = time Power is the scalar product of force and velocity simplified non-calculus calculus P = F∥v P = Fv cos θ P = F · v Where P = power F∥ = component ...

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power physics

discussion summary practice problems power physics Discussion Intro Power is the rate at which work is done or the rate at which energy is transfered from one place to another or transformed from one type to another. P̅ =  ΔW Δt P = dW dt     P̅ = F̅v cos θ P = F · v Power of some things power (W) device, phenomena, process, event gamma ray burster 3.6 × 1039 typical ...

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Conservation Of Energy Problems

discussion summary practice problems Problems practice The diagram below shows a 10,000 kg bus traveling on a straight road which rises and falls. The horizontal dimension has been foreshortened. The speed of the bus at point A is 26.82 m/s (60 mph). The engine has been disengaged and the bus is coasting. Friction and air resistance are assumed negligible. The numbers on the ...

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Conservation Of Energy Practice

discussion summary practice problems Practice problem 1 The diagram below shows a 10,000 kg bus traveling on a straight road which rises and falls. The horizontal dimension has been foreshortened. The speed of the bus at point A is 26.82 m/s (60 mph). The engine has been disengaged and the bus is coasting. Friction and air resistance are assumed negligible. The numbers on ...

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