Question

which statement correctly distinguishes between all mechanical and all electromagnetic waves? mechanical waves carry energy perpendicular to wave motion; electromagnetic waves carry energy parallel to wave motion. electromagnetic waves carry energy perpendicular to wave motion; mechanical waves carry energy parallel to wave motion. electromagnetic waves carry energy through a medium; mechanical waves carry energy through media and space. mechanical waves carry energy through a medium; electromagnetic waves carry energy through media and space.

Explanation:

1. Recall the definitions of mechanical and electromagnetic waves:

• Mechanical waves (e.g., sound, water waves) require a medium (solid, liquid, gas) to travel. They can be transverse (energy perpendicular to wave motion) or longitudinal (energy parallel to wave motion).
• Electromagnetic waves (e.g., light, radio waves) are transverse waves and can travel through a medium (like air, water) or through empty space (vacuum) because they are composed of oscillating electric and magnetic fields that don't need a medium.

1. Analyze each option:

• First option: Incorrect. Mechanical waves can be transverse (energy perpendicular) or longitudinal (energy parallel), and electromagnetic waves are transverse (energy perpendicular). So this swaps the behaviors.
• Second option: Incorrect. Electromagnetic waves are transverse (energy perpendicular), and mechanical waves can be transverse or longitudinal. This misclassifies both.
• Third option: Incorrect. Electromagnetic waves can travel through space (vacuum) and media, but mechanical waves cannot travel through space (they need a medium). So this statement is wrong about mechanical waves.
• Fourth option (the bottom - left one): Correct. Mechanical waves need a medium to carry energy (they can't travel in a vacuum). Electromagnetic waves can carry energy through media (like air, glass) and through space (vacuum, e.g., sunlight reaching Earth through space).

Answer:

Mechanical waves carry energy through a medium; electromagnetic waves carry energy through media and space.