1. What do you meant by vibrations? 2. What is the other name for larynx?
3. Do all animals produce sound by vocal chords?
4. Write the unit of frequency.
5. What do you mean by noise pollution?
6. What is the loudness of a normal conversation?
7. Explain importance of sound in our daily life.
8. Name the organ in human that produces sound. How does it work?
9. Prove that sound travels in solids too.
10. How does loudness of sound is affected by amplitude?

Apositive charge moves in the direction of an electric field. which of the following statements are true? check all that apply. check all that apply. 1.the potential energy associated with the charge decreases. 2. the electric field does positive work on the charge. 3. the electric field does negative work on the charge. 4. the potential energy associated with the charge increases. 5. the electric field does not do any work on the charge. 6. the amount of work done on the charge cannot be determined without additional information.

Arrange the images in order to show how lake-effect snow occurs.

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.