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logic
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It's mine!
What belongs to you but others use it more than you do?
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mail puzzle
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permalink
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rating
3.1/5
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science
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Thunder and lightning
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Why does a flash of lightning take only an instant, while the corresponding thunder can last for a few seconds? You might have expected that that the sound is caused by the flash, and that the thunder should therefore be audible also for an instant.
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mail puzzle
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permalink
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rating
3.1/5
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science
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Voltage voodoo
In the figure, an electrical circuit is drawn. In the middle of the circuit a infinitely long metal bar is placed indicated with the grey circle. In this bar, an oscillating magnetic field is induced by a coil which is attached somewhere to the bar. Two resistors are located in the circuit with values R1 and R2. The alternating voltages V1 and V2 are being measured with two perfect alternating voltages meters.
What is the relation between the two voltages V1 and V2?
a) V1 : V2 = R2 : R1
b) V1 : V2 = 1 : 1
c) V1 : V2 = R1 : R2
d) V1 = V2 = 0
e) something different.
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mail puzzle
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permalink
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rating
3.1/5
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