Consider the following statements:
1. Assertion (A): Transformer is useful for stepping up or stepping down voltages.
2. Reason (R): Transformer is a device used in D.C. circuits.
In the context of the above two statements, which one of the following is correct?
A
Both A and R are true and R is the correct explanation of A.
B
Both A and R are true but R is not a correct explanation of A.
C
A is true but R is false.
D
A is false but R is true.
Correct Answer: Option C
Explanation
1. Statement A (Assertion): A transformer is an electrical device that changes the voltage (and correspondingly, current) of an alternating current (AC). It can indeed be used for stepping up (increasing) or stepping down (decreasing) voltages. So, Assertion (A) is true.
2. Statement R (Reason): Claims a transformer is a device used in D.C. circuits. This is false. Transformers work on the principle of mutual induction, which requires a changing magnetic flux. A changing magnetic flux is produced by an alternating current (AC). Direct current (DC) produces a constant magnetic flux, which cannot induce a voltage in the secondary coil (except momentarily when switched on or off). Therefore, transformers do not work with steady DC. So, Reason (R) is false.
3. Since A is true and R is false, the correct option is (C).