The circuit diagram is shown below
The supply voltage,
Vs=24V Zener voltage,
Vz=10V The value of supply voltage is greater than the Zener voltage.
Hence, the voltage across the load resistance of 5 kΩ will be equal to Zener voltage as they are connected in parallel combination.
Current
IL flowing through the load resistance can be calculated as
IL==2×10−3A=2mA Since, the voltage drop across 5 kΩ is 10 V, then the voltage dropacross 1 kΩ resistance, V′ = 24 − 10 = 14 V
Current flowing through 1 kΩ resistance can be calculated as
I===14×10−3A=14mA From circuit diagram,
I=IZ+IL Iz=I−IL=14−2=12mA Power across Zener diode is
P=Vz×Iz=10×12=120mW Thus, the power across the Zener diode is 120 mW.