Q. A 40 ohm resistor, a 60 ohm resistor, and a 120 ohm resistor are connected in parallel and this parallel group is connected in series with 15 ohm in series with 25 ohm. The whole system is then connected to a 120 volt power source. What is the current running through the 25 ohm resistor?
Q. A beam of light enters the fiber from air at an angle theta1 with respect to the normal. What is theta1 if the light strikes the core-cladding interface at the critical angle theta c?