Discussion
Determine the amount of voltage across resistance R3 for the given circuit.
Answer: A
The resistors R1, R2 and R3 are in series across the 200 V supply, so the voltage drops add up to the supply voltage.
\[ V_{3} = 200 - 60 - 60 = 80\ \mathrm{V} \]
So the voltage across R3 is 80 V, option (A). The values 40 V, 20 V and 120 V would not add up with 60 V and 60 V to the 200 V of the supply. The same rule, that the voltage drops in a series circuit add up to the supply voltage, is Kirchhoff's voltage law. Here R1 and R2 each take 60 V, so together they take 120 V, and the 80 V left over must fall across R3. Since the current is the same in all three resistors, R3 has the largest resistance of the three, because its drop is the largest.
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development