Momentum, Power, energy, spring, Heat engine Study guide II Name______
How much work is done in carrying a 30 kg box up a set of steps which is composed of 12 steps(draw this) which are each 22 cm high,
If it takes 3 seconds to carry the box to the top of the stairs, what is the average Hp used in carrying the box up the steps.
At the top of the stairs is a plateau which is 100 meters long until the box carrier would come to a cliff. How much work is done in carrying the box from the top of the stairs to the edge of the cliff. (Since you are traveling so slowly air resistance can be neglected. )
”Chuck Liddell” is planning to establish a very basic method of sorting out which of the 2000 coeds on the college campus which will be allowed to date him. You see he hangs a spring vertically (up and down) from a very strong tree limb. One end of the spring is attached to the limb and the other he attached a swing seat. His ideal woman is of course his mother (don’t think icky things here) and he knows that she has a mass of 57 kg and cause the spring apparatus to stretch 2.2 cm. One of the “girls” who takes a seat is “Zanadu” who causes the spring seat to stretch 3.5 cm. What is the “weight” of Zanadu?
After marrying Zanadu, Chuck takes the spring down and lays it horizontally on a table and attached firmly to a football. He then stretches spring 30 cm and releases it. The football is observed to pass the origin at 3m/s. What is the coefficient of friction between the ball and the table?(I have not calculated this so it may be a very odd number)
How much work does Zanadu do when she stretches the spring 300 cm?
If she stretches this spring in a time of 3 seconds, how much power does she generate?
A Handsome 3 gram slug is floating on the frictionless surface provided by an air hockey table to the right at 2m/s when it collides with a 2 gram Lovely slug which was moving at 2 m/s to the left. (No question yet).
If the two slugs stick together like a couple of icky middle school kids and move away together, what is their velocity after the collision.
Now consider that the slugs are now billiard balls(not sticky) and after collision they move away from each other. What is the velocity of each ball after the collision?
Michael Moor-ahn the famous political activist has made a new movie. He calls it “To Save a Tree”. It centers on “professor Moor-uhn” making numerous claims. First he claims that he has designed a heat engine which burns coal which produces electric power. The input steam is at 12000F and has an output of 12 0F. It will be located on the beautiful island of “Morondia” which is located at the equator.
Do you see a violation of any of the laws of thermodynamics? Which and why?
He further claims that his plant has a Carnot efficiency of 98%. Any problem with this claim?
Professor Morondia has also claimed to have invented a new stove. All a hungry person must do is place a cold pan of water on the stove and the heat from global warming will spontaneous move toward the pan and boil your soup with no other energy input. Do you see a problem here?
Ok a real heat engine problem.
Z-best power systems have designed a power plant which consumes ordinary household garbage and releases no pollution into our atmosphere. The plant will produce 400 MW of power and have an efficiency of 92%. What rate will garbage are burned if it contains 400J/kg . The heat engine is actually two. The exhaust gas of the first moves into the second in order to more efficiently utilize the energy contained in the garbage. The steam going into the first engine is 3000 K, Exhaust is 2000K, and a pipe carries the heat into a second engine at 1000K and finally exhausts waste heat at 400 Kelvin.