1. What is Sound? Sound is a form of energy which produces a sensation of hearing in our ears. Sound is produced by vibrating objects. Examples include vibrating tuning fork, vocal cords in humans, bells, musical instruments, etc. Vibration: Rapid to-and-fro (back and forth) motion of an object. Short Question: Can sound be produced without vibration? Answer: No, sound cannot be produced without vibration. 2. Medium of Sound The substance through which sound travels is called a medium . Sound can travel through solids, liquids, and gases but cannot travel through vacuum . Process of Sound Propagation: When an object vibrates, it makes the air particles around it vibrate. These air particles move back and forth from their original (rest) position. The vibrating air particles push nearby air particles. This causes the nearby particles to also start vibrating. In this way, vibrations pass from one particle to another. This process continues through the medi...
Acids: An acid is a hydrogen containing substance that is capable of donating proton (hydrogen ion) to another substance. Acids are sour in taste. Acids change the colour of blue litmus to red. They conduct electricity when dissolved in water. Examples: HCl, H2SO4 etc. Some naturally occurring acids are: Natural Source Acids Vinegar Acetic acid Orange and lemon Citric Acid Tamarind (इमली) Tartaric acid Tomato Oxalic acid Curd (sour milk) Lactic acid Ant's sting and nettle's sting Methanoic/formic acid Bases: Bases are the chemical substances that p...