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okay first q....

1) Two lightbulbs, one rated 30 W at 120 V and another rated 40 W at 120 V, are arranged in two different circuits, if connected in series to a 120 V source, what is the resistance and current of each lightbulb?

well i thought since they are in series, the current had to be the same throughout, the Voltages had to add up to total V of the circuit, except with the different wattages, I have little idea where to start because I cant use P=V^2/R because Voltages of each arent teh same and I cant use P=(I^2)R because I dont think I'm given enough info on how to calc. the current of each...can someone at least get me started? or see if there are any misconceptions?

2)Determine the potential difference through which an electron must be accelerated in the electron gun in order to have a speed of 6E7 M/S

qV = 1/2mv^2 correct? i just wanted confirmation...

and suppose there were two plates with a potential difference of 200, separated by .012 M and had a length of .04 M, how would I calculate the time required to move through the plates and the electron's vertical displacement?...someone please just throw me a bone here?

Thanks muchooo to whoever can help

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# Homework Help: Questions on Electrostatics/Electricity/Stuff?

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