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physics electricity question

The question states:
"Resistance of filament lamp at its working temp is 11 ohms.
Filament has length 0.36m and diameter of 32μm.

Cal resistivity of the metal that is used for the filament when the lamp is at its working temp... give an appropriate unit for the answer"

First of all, answer for the area A = 8.0 x 10^-10 m^2

I don't get how that was the area, i did pi r^2 and got 5.02x10^-5...
You must be typing it wrong into your calculator. I did pir^2 and got 8x10^-10
μ = 10^-6
Radius = 16 x 10^-6
pie x (0.5(32x10^-6))^2
Not sure what u did do get that answer but if you put ((32x10^-6)/2)^2 * pi u get their answer :smile:
Reply 5
ohhhh, thanks guys.
i did make an calculation error, no wonder i got it wrong.

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