A sinusoidal voltage source (dependent or independent) produces a voltage that varies as a sine wave with time. A sinusoidal current source (dependent or independent) produces a current that varies with time. The sinusoidal varying function can be expressed either with the sine function or cosine function.

How do you make a sinusoidal voltage?

As the coil rotates the voltage decreases according to the sine of the angle until the conductor is parallel to the magnetic field. Further rotation then increases the voltage until once again it is at a maximum (but in the opposite direction). For each revolution a complete sine wave is generated.

Is DC voltage sinusoidal?

DC circuits have a unidirectional flow of current and like AC it is not changing the direction periodically. Waveform of DC is a pure sine wave. As you can see, the voltage is constant with respect to time.