Engineering Board Exam Reviewer · Energy and Power · hard
A series circuit has V=24 V and R1=100, , and R1 dissipates 4 W. What is R2?
- 120,
- 200,
- 20,
- 80,
Answer
C. 20,
Solution
P1=I2R1 I=sqrt(4/100)=0.2 A. RT=V/I=24/0.2=120, , so R2=120-100=20, .
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