Answer:
voltage= 17.88volts
current= 0.04 amps
Step-by-step explanation:
Step one:
given data
resistance R=400 ohms
Power P= 0.8W
a. What is the maximum voltage that can be applied across this resistor without damaging it?
the expression relating power and voltage is
P=V^2/R
substituting we have
0.8=V^2/400
V^2=0.8*400
V^2=320
V=√320
V=17.88 volts
the maximum voltage is 17.88volts
b.What is the maximum current it can draw?
we know that from Ohm' law
V=IR
17.88=I*400
I=17.88/400
I=0.04amps