[PHYS] Example Question: The quantity of charge q (in coulombs) that has passed through a surface of area 2.05 cm2 varies with time according to the equation q = 7t^3 + 3t + 6, where t is in seconds.

Example Question

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# Question

The quantity of charge q (in coulombs) that has passed through a surface of area 2.05 cm^2 varies with time according to the equation q = 7t^3 + 3t + 6, where t is in seconds.

(a) What is the instantaneous current through the surface at t = 0.900 s?

(b) What is the value of the current density?

 

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# Explanation

(a) What is the instantaneous current through the surface at t = 0.900 s?

(b) What is the value of the current density?

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