Assertion (A): In our houses, the current in AC. electricity line changes direction 60 times per second.

Correct Option

Option (D):

Assertion (A) states that the current in an AC electricity line changes direction 60 times per second. In India, the standard frequency of alternating current (AC) supply is 50 Hz. One complete cycle of AC involves the current flowing in one direction and then reversing to flow in the opposite direction. This implies that for every cycle, the direction of the current changes twice. Therefore, for a 50 Hz supply, the current changes direction 2 × 50 = 100 times per second. Hence, Assertion (A) is false.

Reason (R) states that the frequency of alternating voltage supplied is 50 Hz. This statement is factually correct for the standard AC supply in India. Hence, Reason (R) is true.

Given that Assertion (A) is false and Reason (R) is true, option 4 is the correct choice.

Incorrect Options

Options 1, 2, and 3 are incorrect as they do not accurately represent the truthfulness of both Assertion (A) and Reason (R).

• Option 1 posits that both A and R are true and R is the correct explanation of A. This is incorrect because Assertion (A) is false.
• Option 2 posits that both A and R are true but R is not the correct explanation of A. This is incorrect because Assertion (A) is false.
• Option 3 posits that A is true but R is false. This is incorrect because Assertion (A) is false and Reason (R) is true.