7. Amplitude is the part of a wave that changes the volume of a sound. Amplitude in a wave is the maximum displacement or distance moved by a point on a vibrating wave measured from its equilibrium. The volume of a sound is proportional to the amplitude of the sound wave.
8. Wavelength is the part of a wave that can make a wave have a high squeaky sound. The shorter the wavelength the higher the frequency, and therefore the higher the pitch of the sound. In an art cell short waves sound have pitch while the long waves sound have high pitch.
9. Crest is part of a wave that is the highest point on a wave. A transverse wave is such that particle vibrations is perpendicular to the direction of the wave motion, the particles vibrate to the highest point called crest.
10. Trough is a part of a wave which is the lowest point on a wave. Trough is the lowest point reached by the vibrating particles in a transverse wave. The wave motion is perpendicular to the vibration of particles which creates highest points (crests) and lowest points (troughs)
11. Sound waves are longitudinal waves and mechanical waves. Longitudinal waves because the vibration of particles in sound waves is parallel to the wave motion. They are mechanical waves because sound waves require material medium for transmission unlike electromagnetic waves which do not require material medium for transmission.
12. When a sound wave travel from a solid to liquid its speed would decrease. This is because in liquid molecules are loosely packed than in solids due to weak inter molecular forces between them, therefore it takes more time for the molecules to collide (vibrate) with the neighboring molecules compared to the case in solids. This reduces the speed of sound in solids.
13. As frequency increases, the wavelength decreases. The speed of a wave is given by multiplying frequency by wavelength, therefore at constant speed, increase in frequency causes a decrease in wavelength. Wavelength is therefore inversely proportional to frequency of a wave.
14. In a transverse waves, the wave motion is perpendicular to the vibration of particles. The particles vibrate reaching the highest points called crest and the lowest points called troughs. At the crests and troughs the displacement of particles is maximum
15. In a longitudinal wave the wave motion is parallel to vibration of particles. In longitudinal waves particles vibrate parallel to the direction of wave motion creating regions of rarefactions and compressions. Compressions are the regions where the particles are close together while the rarefactions are regions where particles are furthest apart.
16. Sound travel faster in solids than in air or gases. This is because the distances between molecules in solid is very small meaning that solid are more dense compared to gases. Due to this packaging the molecules collide more faster, that is it takes less time for a molecule to collide with its neighboring molecules, this makes sound travel faster in solids than in liquids and gases.
17. You cant hear any sounds in a near empty regions or space (vacuum). this is because sound is a mechanical wave and requires material medium for transmission. Sound travels through vibration of particles (atoms and molecules) in a medium such as solids,liquids and gases. Since in space there is no air or other particles it cannot therefore travel.
18. A transverse wave is a wave where the direction of wave motion is perpendicular to the vibration of particles. It shows highest points called crests and the lowest points called troughs. As shown
19. A longitudinal wave is a type of a wave where the direction of the wave motion is parallel to the vibration of particles. Particles vibrate creating a region of compressions and rarefactions As shown.