A circuit element hiden inside a paper bag draws a current that varies with time

Question

A circuit element hiden inside a paper bag draws a current that varies with time t (in seconds) according to the current function i(t) = 0.032 sin(2350·t) Amps, while the voltage drop across this element is given by the function v(t) = 8.27 cos(2350·t) Volts.     

Determine if the hidden element is an inductor or a capacitor, and what is its value?

If the circuit element could be either a capacitor or an inductor, state both possible values below (giving the capacitance value first, and providing correct units for each answer).
If the circuit element must be a capacitor (or must be an inductor), enter that single possible value (with correct units) in both boxes.

Explanation / Answer

capacitor current leads the voltage and inductor current lags the voltage.
this question is a case of current lagging the voltage.( sin lags cos by 90o, sin = cos(-90) )

V = L di/dt

8.27 = L x 2350 x0.032

L = 0.11 H

P.S. If you have problem with leading and lagging, just remember that V=Ldi/dt in inductor and i=CdV/dt in capacitor. U can see that only one of them matches the current and voltage expressions(with proper signs)

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