that transfers ercray through matter or space. 3. Contrast how you would move a spring to make a transverse wave with how you would move a spring to make a longitudinal wave. 4. Give an example of a mechanical wave that is also a longitudinal wave. 5. Are seismic waves (waves throughout the Earth's crust)mechanical waves? How about sound? Light (electromagnetic waves)? In each case , if the wave is a mechanical wave, identify the medium. 6. Describe how the world would be different if all waves were mechanical waves. 7. The average speed of sound in water is 1500m/s How long would it take a sound wave to travel electromagnetic wave (light) travel in Conversions: ugght is 3times 10^6m/s.14aof for val units whole bunity voler in molars),Tris distance 18 hooras a li

1. **Definition of a wave:** A wave is a disturbance that travels through space and time, transferring energy from one place to another without transferring matter.<br /><br />2. **Mechanical wave:** A mechanical wave is a wave that requires a medium (a substance like solid, liquid, or gas) to travel through. It propagates by causing the particles in the medium to vibrate or oscillate. Examples include sound waves, water waves, and seismic waves. A mechanical wave *does not* transfer matter through space; it transfers energy through the movement of matter.<br /><br />3. **Transverse vs. Longitudinal Waves in a Spring:**<br /><br />* **Transverse Wave:** To create a transverse wave in a spring, you would move one end of the spring up and down or side to side, perpendicular to the length of the spring. The wave pattern travels along the spring, but the individual coils move perpendicular to the direction of wave propagation. Think of shaking a rope.<br /><br />* **Longitudinal Wave:** To create a longitudinal wave in a spring, you would push and pull one end of the spring along its length. This creates compressions (areas where the coils are close together) and rarefactions (areas where the coils are spread apart) that travel along the spring. The coils vibrate parallel to the direction of wave propagation. Think of a slinky being pushed and pulled.<br /><br />4. **Example of a Mechanical and Longitudinal Wave:** Sound waves are an example of a mechanical wave that is also a longitudinal wave. Sound travels through a medium (like air, water, or solids) by creating compressions and rarefactions of the particles in the medium.<br /><br />5. **Types of Waves:**<br /><br />* **Seismic Waves:** Seismic waves are **mechanical waves**. The medium is the Earth's crust and interior.<br />* **Sound Waves:** Sound waves are **mechanical waves**. The medium can be air, water, solids, or other materials.<br />* **Light Waves (Electromagnetic Waves):** Light waves are *not* mechanical waves. They are electromagnetic waves and can travel through a vacuum (empty space). They do not require a medium.<br /><br />6. **A World with Only Mechanical Waves:** If all waves were mechanical waves, the world would be drastically different. Communication would be limited by the need for a physical medium. We wouldn't have radio, television, or cell phones, as these rely on electromagnetic waves. We wouldn't be able to see the sun or stars, as light is an electromagnetic wave. Essentially, any information or energy transfer that relies on electromagnetic waves would be impossible.<br /><br />7. **Sound Travel Time in Water:**<br /><br />* **Speed of sound in water:** 1500 m/s<br />* **Distance:** 9.0 km = 9000 m (since 1 km = 1000 m)<br /><br />* **Time = Distance / Speed**<br />* **Time = 9000 m / 1500 m/s = 6 seconds**<br /><br />It would take 6 seconds for a sound wave to travel 9.0 km in water. The information about the speed of light and the 18 hours is irrelevant to this specific question.<br />