JEE Main 2021 · 25 February · evening · Single correct · +4 / −1
Match List I with List II.
Choose the correct answer from the options given below :
| List I | List II | ||
|---|---|---|---|
| (a) | Rectifier | (i) | Used either for stepping up or stepping down the a.c. voltage |
| (b) | Stabilizer | (ii) | Used to convert a.c. voltage into d.c. voltage |
| (c) | Transformer | (iii) | Used to remove any ripple in the rectified output voltage |
| (d) | Filter | (iv) | Used for constant output voltage even when the input voltage or load current change |
- (a) (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)
- (b) (a)-(iii), (b)-(iv), (c)-(i), (d)-(ii)
- (c) (a)-(ii), (b)-(i), (c)-(iv), (d)-(iii)
- (d) (a)-(ii), (b)-(i), (c)-(iii), (d)-(iv)
Answer and solution
Answer (a) (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii)
Solution
Physics sir · 2 steps
Think of a DC power supply as a chain: transformer, rectifier, filter, stabilizer. Each does one job.
- Follow the chain. A power supply turns mains a.c. into a steady d.c. in four stages. Each stage fixes one problem left by the stage before it.
Device What it does Match Transformer Steps the a.c. voltage up or down to the level needed (c)-(i) Rectifier Uses diodes to let current flow one way only, so a.c. becomes d.c. (a)-(ii) Filter Smooths out the ripple left in the rectified output (d)-(iii) Stabilizer Holds the output voltage constant when the input or the load changes (b)-(iv) - So. The matching is (a)-(ii), (b)-(iv), (c)-(i), (d)-(iii), which is option (a).
The idea to keep. Remember the order transformer → rectifier → filter → stabilizer. The rectifier only makes the current one-way; the filter is what removes the ripple.
Answer from the NTA final answer key. Solution by PrepWiser.