A flashlight bulb rated at 1.4W and 4.0V is operated by a 9.0V battery. To light the bulb at its rated voltage and power, a resistor is connected in series as shown in the figure. ( i dont know how to paste the picture but its only a resistor and then light bulb in series with a 9v battery attached)
What value should the resistor have?
Express your answer using two significant figures.
The Attempt at a Solution
I know that when resistors are in series the current is equal throughout.. so i used P=IV to solve for current, then pluggled that into V=IR using to find R but that is obviously wrong i am going crazy!