Physics

Problem

A circuit carries a current described by

I(t)=\begin{cases} 3t & 0\le t\le 2\,\text{s}\\ 12-3t & 2\,\text{s}<t\le 4\,\text{s} \end{cases}

where

I

is in amperes and

t

in seconds. At what single time

t

between

0

and

4\,\text{s}

has exactly one-half of the total charge that will pass through the circuit already passed? a)

1.41\,\text{s}

2.0\,\text{s}

3.0\,\text{s}

2.5\,\text{s}