Infra-Red (IR) Detectors:
An IR detector has an impedance of Z= (400+j200) ? . During design tests the detector current is measured as 4 µA.
What is the output voltage of the detector?
Optic lens:
Using a converging lens of focal length f= 10 cm, we want an object to appear on the screen twice as big as its original size.
Where is the object to be located in front of the screen (real image)?