Question 1:
Does the distance of a sound source from the reflecting surface have any effect on the echo produced? Give your opinion.
Answer:
Yes, distance of source that is far from the surface causes sound to lose energy, resulting in a weaker echo.
Does the distance of a sound source from the reflecting surface have any effect on the echo produced? Give your opinion.
Answer:
Yes, distance of source that is far from the surface causes sound to lose energy, resulting in a weaker echo.
Question 2:
Why is echo heard repeatedly in a cave?
Answer:
The rough walls of a cave causes reflection of sound in all directions. This causes echo to be heard repeatedly.
Why is echo heard repeatedly in a cave?
Answer:
The rough walls of a cave causes reflection of sound in all directions. This causes echo to be heard repeatedly.
Question 3:
State two uses of ultrasound.
Answer:
(i) To examine condition of foetus in the womb.
(ii) To estimate depth of sea.
State two uses of ultrasound.
Answer:
(i) To examine condition of foetus in the womb.
(ii) To estimate depth of sea.