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The vertical position $y$ has the same units as the amplitude $A$ because the sine function is a dimensionless, unitless quantity. In the equation $y(x,t)=A\sin(kx-\omega t+\phi)$, the argument of the sine function evaluates to a pure number in radians, which has no physical units.

Conditions: Applies to the traveling sinusoidal wave equation $y(x,t)=A\sin(kx-\omega t+\phi)$.; The sine function outputs a dimensionless number.; $A$ is measured in distance units (e.g., meters).

The vertical position $y$ has the same units as the amplitude $A$ because the sine function is a dimensionless, unitless quantity. In the equation $y(x,t)=A\sin(kx-\omega t+\phi)$, the argument of the sine function evaluates to a pure number in radians, which has no physical units.

Conditions: Applies to the traveling sinusoidal wave equation $y(x,t)=A\sin(kx-\omega t+\phi)$.; The sine function outputs a dimensionless number.; $A$ is measured in distance units (e.g., meters).