Saved Bookmarks
| 1. |
A bat flying above lake emits ultrasonic sound of 100 kHz ,When this wave falls on the water surface, it is partly reflected and partly transmitted .The wavelengths of the reflected and the transmitted waves are (The speed of sound in air is 340 m/s and in water is 1450 m/s)A. ` 6.8 ` mm and 2.9 mmB. 3.4 mm and 1.45 cmC. 3.4 mm and 7.8 mmD. 6.8mm and 1.45 cm |
|
Answer» Correct Answer - B |
|