The current to a light-emitting diode (LED) of resistance 250 Ω has to be limited to 5 mA. What resistor should be connected in series with the LED when it is connected to a 5 V DC supply? A potential...

The current to a light-emitting diode (LED) of resistance 250 Ω has to be limited to 5 mA. What resistor should be connected in series with the LED when it is connected to a 5 V DC supply?

A potential divider circuit is to be used to reduce a 24 V DC supply to 5 V. What resistors should be used if the circuit current should not exceed 10 mA?