0What are the differences between Transverse and Longitudinal waves?
| Transverse waves | Longitudinal waves |
| The particles of the medium vibrate or oscillate perpendicular to the direction of motion of the wave. | The particles of the medium vibrate parallel to the direction of motion of the wave. |
| Crests and Troughs formed when transverse waves are passing through a medium. | Compressions and rarefactions are formed when longitudinal waves are passing through a medium. |
| Example: Waves on a string, light waves, microwaves etc | Example: Vibration on spring, sound waves etc |
Describe how waves move on the surface of the water?
When the surface of the water is disturbed by dropping a small stone, a circular ring is immediately formed with its centre at the point of disturbance. This is called a ripple or a water wave. The radius of this cirlce goes on increasing, indicating that the wave or disturbance is moving with a constant speed in all the directions. It is observed that only the ripples on the surface, i.e. the disturbance moves through the water, not the water particles. In fact, the particles oscillate to and fro about a certain position which is called the mean position. This results in the formation of crests and troughs in the wave.
Describe the motion of molecules in the air when a metallic strip is vibrated?
If the free end of a metallic strip is vibrated, it creates a disturbance in the surrounding air. The air molecules get separated with equal space between them. Air being a homogenous medium, the density of molecules is the same everywhere. When the strip moves forward, the molecules are pushed forward coming closer to one another—the space between the molecules decreases and hence density increases. When the strip moves backwards, the molecules also move backwards, and the separation between them increases, causing a decrease in density. The region of the air where density is higher is called compression or condensation, whereas the region of lower density is called rarefaction.
What is a wave?
A wave is a disturbance in a medium and moves ahead in all directions with constant speed. When a wave progresses, the particles in the medium, do not move from place to place but simply oscillate about their mean positions.
How do particles move in a medium when a transverse wave is created?
When a transverse wave passes through a medium, the particles of the medium oscillate perpendicular to the direction of the motion of the wave causing crests and troughs.
How do particles move in a medium when a transverse wave is created?
When a longitudinal wave passes through a medium, the particles of the medium oscillate parallel to the direction of the motion of the wave causing compressions and rarefactions.
What is the difference between light waves and sound waves?
| Light waves | Sound waves |
| They are transverse waves | They are longitudinal waves |
| They can travel through a vacuum. | They require a medium for transfer. |
What is the nature of the image of a water wave on the wall?
When the image of a water wave is formed on a wall, alternate dark and bright concentric rings are observed corresponding to the crests and troughs on the surface of the water.
