1. The repetition of sound which is reflected from an object is referred to as _______.   the amplitude   an echo   the pitch   Hint Half-n-half Clue   2. The apparatus used in a ship to find out the depth of the sea underneath is called _______.   bell jar   sonar   tuning fork   Half-n-half Clue   3. The sound of thunder is heard 10 s after the flash of lightning. If the speed of sound in air is 330 m/s, then the cloud is at a distance of _______.   33.0 m   66.0 m   1650 m   3300 m   Half-n-half Clue   4. The part of the inner ear shaped like a snail is called the _______.   hammer   cochlea   eardrum   Half-n-half Clue   5. The approximate speed of sound in air is _______ m/s.   1600   5000   3 × 108   330   Half-n-half Clue   6. The number of sound vibrations per second is called _______.   frequency   time period   amplitude   Half-n-half Clue   7. Sound can travel through vacuum.   True   False