1. The problem statement, all variables and given/known data The current through a 100 microfarad is i(t) = 50 sin(120*pi*t) mA Calculate the voltage across it at t = 1 ms. Consider zero initial voltage. 2. Relevant equations v(t) = (1/c) integral of i(t) from t = 0 to t = t 3. The attempt at a solution Am getting v(t) = - 1.326 ( cos(120*pi*t) - 1 ) V which gives v(1*10^-3) = -2.87 * 10^(-5) V But book is saying the voltage should be 93.14 mV Can any confirm if book answer is correct? I did the problem like 100 times, and still same value. I considered that given current in mA so I multiplied by 10^-3, and considered the 10^-6 from micro farad. integral of sin(120*p*t) is -cos(120*pi*t) / (120*pi) I have no idea where is my mistake.