🔍 Key Concepts
• Sine wave as a smooth, repetitive oscillation
• Relationship between circular motion and the sine function in trigonometry
• Difference between periodic (regular, repeating) waves and random variations
💭 Think About
• Which option connects a wave’s amplitude to the mathematical sine function or circular motion?
• Which choices describe behavior that is irregular or not strictly tied to a single smooth mathematical function?
• How would you graph a pure AC voltage or current over time, and which description best matches that picture?
✅ Before You Answer
• Eliminate any choice that mentions random or non-repeating behavior, since a sine wave is highly regular and predictable.
• Check which option clearly ties the wave’s amplitude to sine or to a point moving on a rotating circle at constant speed.
• Be careful not to confuse the sine function with the tangent function; they describe different mathematical relationships.