No, the amplitude of a sine wave is not equal to the radius of a circle. While both concepts involve the notion of distance or magnitude, they are not directly related.
In the context of a sine wave, the amplitude refers to the maximum displacement or magnitude of the waveform from its equilibrium position. It represents the maximum value that the waveform reaches in either the positive or negative direction. The amplitude is typically denoted by the letter "A" and determines the height or "peak" of the wave.
On the other hand, the radius of a circle refers to the distance from the center of the circle to any point on its circumference. It is a fundamental property of a circle and is constant for all points on the circle. The radius is denoted by the letter "r" and defines the size of the circle.
While both the amplitude of a sine wave and the radius of a circle involve the concept of magnitude or distance, they have different interpretations and applications in their respective domains.