# determine the current flowing thru an element

• January 6th 2011, 11:00 AM
bigwave
determine the current flowing thru an element
determine the current flowing thru an element is the charge flow is given by:

(a) $q(t) = (3t+8) mC$

assume the way to do this is just

$
i= \frac{dq}{qt}=\frac{d}{dt} (3t+8)mC= \boxed{3mC}
$

assume we keep the same units for answer.
there are 4 more of these
just seeing if doing what should be.(Cool)
• January 6th 2011, 11:05 AM
Ackbeet
Looks good to me, except the units are incorrect. You should have some version of amps going on there for the current.
• January 6th 2011, 11:33 AM
bigwave
(b)
oops... yes it should $3m[A]$

(b)
$q(t) = (8t^2+4t-2)[C]$

so thus for i

$i=\frac{dq}{qt}=\frac{d}{dt} (8t^2+4t-2)C=(16t+4)[A]$
• January 6th 2011, 11:34 AM
Ackbeet
Sure.