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1

For switched mode power supply with a given load and operating with 240VAC input, the power supply 'draws' approximately 1/2 the AC current than when operated with 120VAC input all else being equal. Indeed, the AC input current varies inversely with the AC input voltage. This can be confirmed with a variable autotransformer and AC ammeter. is it true ...


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The mass will not move at constant speed, it will be accelerated because of the Force. As the mass accelerates, it gets more work from the same force, that is, the power increases (remember: $P=F.V$). This power is giving an accelerated amount of work. Even if the force is constant, the power it produces becomes unbounded until it the speed becomes ...


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You are assuming that your power source can supply a constant force $F$ while outputting a constant power. But you have already shown in the question this is not right, because the power outputted by the source is $F v$ where $v$ is the speed of the thing being pushed.


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Yes, it is! When the electromagnetic wave reaches an antenna, electrons in the antenna will be accelerated and there will be a current. This current creates a secondary electromagnetic wave, which travels in all directions. It will certainly hit other antennas in the vicinity. So, the signal obtained by each antenna will vary dependent on the surroundings. ...


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You're making this slightly more difficult than it needs to be with TW-h units, although there's nothing incorrect about the approach. Simply converting to averages makes it much nicer. To do this, divide your number by the number of hours in a day and the number of days in a year. You get around 17.1 TW. This is the average energy consumption of humans in ...


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The British thermal unit (BTU or Btu) is a traditional unit of energy equal to about 1055 joules (ref). A propane torch rated at 200,000BTU will contain this amount of energy in total. The rate at which it supplies this energy is down to how you. In a propane torch, you can control the rate at which the gas is burned. Or you can burn it all at once ...


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It's a little bit hard to follow your reasoning. Let me try to give the method I would use - simple balance of energy. If the car reaches a velocity $v$ after time $t$, the power of the engine will have been used mostly for five components: Kinetic energy of car: $\frac12 m v^2$ Rotational kinetic energy of tires: $4 \times \frac12 I_t \omega_t^2$ ...


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There are many variables that come into play in an armwrestling match, but one answer as to why a person with a larger hand and wrist has an advantage in armwrestling has less to do with strength, and more to do with leverage. In armwrestling, you and your opponent lock hands and attempt to pin each other to a pad on either side of the table. To pin your ...


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"Stange" harmonics cannot appear. Two 50Hz sinus waves always produce another 50Hz sinus wave : $$cos(\omega t)+cos(\omega t+\phi)=2cos(\omega t+\frac{\phi}{2})cos(\frac{\phi}{2}) $$ About synchronization, you should remember that the voltage in the network is fixed, and thus only the current changes. I don't see any problem with combining two different ...



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