An object is placed perpendicular to the principal axis of a concave lens of focal length   5cm. Find the position of the image. The distance of object from the lens is 10cm.

You have a resistor and a capacitor of unknown values. first, you charge the capacitor and discharge it through the resistor. by monitoring the capacitor voltage on an oscilloscope, you see that the voltage decays to half its initial value in 2.70 miss . you then use the resistor and capacitor to make a low-pass filter. what is the crossover frequency fc?