1. Sound can be reflected as well as refracted.   True   False   2. A _______ note is the lowest note obtained on blowing gently across the top of a test-tube.   overtone   harmonic   fundamental   Hint Half-n-half Clue   3. An airtight bell-jar is inverted on a platform connected to a vacuum pump. An electric bell fitted into the jar is operated but its sound cannot be heard. This is because sound cannot travel through _______.   glass   air   vacuum   Half-n-half Clue   4. Sounds travels faster in air as compared to water.   True   False   5. The sound of thunder is heard 7 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 _______.   47.1 m   94.3 m   1155 m   2310 m   Half-n-half Clue   6. The part of the inner ear shaped like a snail is called the _______.   eardrum   cochlea   hammer   Half-n-half Clue   7. Echoes are caused by _______ of sound.   refraction   rarefaction   reflection   Half-n-half Clue