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Transcribed Image Text:The quantity of charge q (Coulomb) passing through a surface of area 5 cm changing
with time as q = 4t + 5t + 6 (t is in units of seconds). Find the current density at
t 4 s.
a) J = 8,50 x 104 A/m2
b) J = 1,77 x 105 A/m2
c)J = 2,83 x 10S A/m2
d) J = 3,94 x 10$ A/m2
e)/ = 5,08 x 10s A/m2
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