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Great problem! Simple to state, incredibly complex to solve. I have three suggestions: I'm not sure that it's a good idea to consider an infinite cylinder. It will have an infinite mass an might just sit there. Your question is not formulated very precisely. To study the time evolution of a dynamical system you need to fully specify it's initial ...


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When you put a pot of water on the stove and turn the burner on, the heat source of the stove gets hot relatively fast, but the water takes a while to boil. For multiple reasons it takes a while for the water to heat up*, or in other words for the heat of the burner to be transferred throughout the pot of water. When you add the ice cube to the boiling ...


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Here, the boiling point of water is is 373K and the temperature of ice is smaller than 273K. When we boil, the water is bought to 373K and when the ice is dropped into the cup, assuming the temperature of ice is 273K, The heat is transferred from the water(The Hotter substance) to the ice(The colder substance) until their temperature is equal that is ...


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Was the container of boiling water still being heated when she put the ice cube in? If not, the water will stop boiling even without the ice cube as the container loses heat. If so, you could (with enough room around the ice cube) have boiling water near the container wall and non-boiling water near the ice cube. The water will not all be at the same ...


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i think,it really depends on the quantity you take!!! In simpler way the heat from water is transferred to ice whic result melting of ice. If u further heat the container the water will boil.


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Friction is terribly difficult to estimate. If you could, you could calculate the speed by measuring the power input and deducting the static losses. What tools do you have available? If you have an oscilloscope, display the current input as a function of time. There will probably be a variation in the resistance over the cycle that will repeat and you ...


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Not sure about this - best guess is that you have observed the formation of an irrotational vortex. When you stir, the liquid tends to rotate as a rigid body. When you stop stirring, then In the absence of external forces, a vortex usually evolves fairly quickly toward the irrotational flow pattern, where the flow velocity u is inversely proportional ...


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You can only measure a part of EU compliance. By using your utility meter and measuring the difference between the power consumed over say 10 minutes with the appliance on and off (with everything else in the house as off or steady as possible), you can measure consumed power. However, that's just one part of EU compliance. The other is power factor. ...


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Your requirement that the measurement be made with equipment available in a kitchen is a severe constraint as I can't think of any way of measuring the electrical power supplied. If it's impossible to measure the electrical power in then the only other approach is to measure the thermal power out - i.e. measure the heat produced by the appliance. Given that ...


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The easiest way would be to use an energy monitor device (the most popular one seems to be the Kill-A-Watt but there are others). They simply plug into the wall and then you plug your appliance into it. It displays instantaneous voltage, current, power, power factor, etc. and can keep total energy over time. Another option would be to buy an electric ...


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You have a rather precise power meter in your home, which is a "gift" of the electrical power company. Turn off every other load that is connected to that power meter and do your measurement. Alternatively, you can invest $20 in an electronic power meter that is available online and in many stores.


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The key to understanding EMP is that this is an induced effect, so you need rapid changes in magnetic field, $\frac{dB}{dt}$. In order to generate a rapidly changing field, you have to have a rapidly changing current in an inductor - as you may recall, $$V = -L \frac{dI}{dt}$$ For this rapid change in current you not only need a high voltage - you need a low ...



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