Calculate Charge Entering Element 0-2 Sec: Simple?

[faraznizamani]

This is bugging me for some reason .. can anyone help me with this ?


the current flowing through an element is
i= {2A, 0<t<1
2t^2, t>1}
calculate the charge entering the element from t=0 to t=2 second

 

[CompuChip]

What is the relation between charge, current and time?

 

[faraznizamani]

I have no other data regarding the question :/ can you help me ?

 

[CompuChip]

Well, current is simply a moving charge. In fact it is defined as the rate at which charge passes:
$$I = \frac{\Delta Q}{\Delta t}$$
or, in the limit of vanishing $\Delta t$,
I(t) = dQ/dt (the derivative).

Try integrating both sides of that equation.