Im new here so please go easy

I have got a piece of work to do regarding op amps (integrator and differentiator circuits)

I have to use my own figures to show how the op amp works

I understand that to work out voltage out = RC dvin/dt

Say for example my Capacitor is 4.7mf and I have 35V input aswell as a 1kohm resistor, I got 1000*0.0047 35v/??

How do I work out the time, what has the time got to do with it?

Thanks in advance

Kyle