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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).

To check the units of the sine argument $kx-\omega t+\phi$, assign the units of each variable: $k$ is in rad/m, $x$ is in m, $\omega$ is in rad/s, $t$ is in s, and $\phi$ is in rad. Multiply the units for $kx$ and $\omega t$ to see that meters and seconds cancel out, leaving radians.

Conditions: Applies to the traveling sinusoidal wave equation $y(x,t)=A\sin(kx-\omega t+\phi)$.; $k$ has units rad/m.; $x$ has units m.; $\omega$ has units rad/s.; $t$ has units s.; $\phi$ has units rad.

To check the units of the sine argument $kx-\omega t+\phi$, assign the units of each variable: $k$ is in rad/m, $x$ is in m, $\omega$ is in rad/s, $t$ is in s, and $\phi$ is in rad. Multiply the units for $kx$ and $\omega t$ to see that meters and seconds cancel out, leaving radians.

Conditions: Applies to the traveling sinusoidal wave equation $y(x,t)=A\sin(kx-\omega t+\phi)$.; $k$ has units rad/m.; $x$ has units m.; $\omega$ has units rad/s.; $t$ has units s.; $\phi$ has units rad.

The phase constant $\phi$, also called phase shift or phase constant, measures where the oscillation started in the cycle. For the displayed wave equation, it is restricted to the interval $0 \leq \phi < 2\pi$ rad and must be expressed in radians.

Conditions: Applies to the phase constant $\phi$ in the traveling sinusoidal wave equation.; $\phi$ must be in radians for the equation.; The allowed range is $0 \leq \phi < 2\pi$ rad.

The phase constant $\phi$, also called phase shift or phase constant, measures where the oscillation started in the cycle. For the displayed wave equation, it is restricted to the interval $0 \leq \phi < 2\pi$ rad and must be expressed in radians.

Conditions: Applies to the phase constant $\phi$ in the traveling sinusoidal wave equation.; $\phi$ must be in radians for the equation.; The allowed range is $0 \leq \phi < 2\pi$ rad.