Question

The diagram shows the magnificent dome at Gol Ghumbaz at Bijapur. A boy standing at A whispers, and it is clearly heard at B across the huge dome. [Speed of sound is 330 ms⁻¹]

Assertion (A): The distance travelled by sound waves (x + y) should be < 33 m.

Reason (R): Sound reflected within 0.1 s is not heard by humans.

विकल्प

• A and R are true, and R is the reason for A.

• A and R are true, and R is not the reason for A.

• A is true, but R is false.

• A is false, but R is true.

Answer 1

A is false, but R is true.

Explanation:

The assertion is false: for an echo to be heard, the reflected sound must travel at least 330 × 0.1 = 33 in total. The reason is true because a reflection heard in less than 0.1 s is not heard as a separate echo.