Question

When Neil Armstrong and Edwin Aldrin landed on moon, they could see each other but could not listen each other without a radio. This is because

• A. their ear drums were not working on moon.
• B. light and radio waves can travel through vacuum but not the sound wave.
• C. they were compelled to use radios to record their conversation.
• D. there was no material medium to transport sound

Answer 1

Answer: (B), (D)

there was no material medium to transport sound

Explanation for correct option:

Option(B): Light waves and sound waves are electromagnetic waves they need no medium to travel.

Option(D): Sound wave needs a material medium to travel but there is no material medium hence they were unable to listen to each other.

Explanation for incorrect option:

Option(A): This option is incorrect because eardrums do not affect by a change in place.

Option(C): This option is incorrect because they were not compiled by anybody else.

Hence, options (B) and (D) are correct.