Question

4) A cylindrical copper cable carries a current of 1200 A. There is a potential difference of 16 mv between the two points on the cable that are 24 cm apart. The number of carriers per unit volume of the current in the wire is 6.95*10^28

a) Find the radius of the cable

b) Find the average current density in the cable

c) What is the drift velocity of the current ?

Answer 1

Salution » I-1200 Remember Scopper 0 0.017 24CM Va 16mv. (2) In R -3 16410 v 4x10n R-V v I 12x102 Remember R= pl (lesistivity of Copper wire = 0.02 A- SI R 0.017x24x102 3x105 А 0.30610 Tr? = Boom? r = 97.45 r = 9.8M b) Current density (J) = I A 1200 = 3.9 Amp Bob m2 Scanned by TapScanner

I = neava J I A nevd J= neva Ju lurrent density N = number of Carriers per mit Veelime Vda drift velosity, Va= 3 me. 3.9 Go95X 1028x1,6x109 3.9 11.12 X10 ud 0:35x10 m/s Scanned by TapScanner