The dependent variable is the one that changes as a result of the independent variable. The spectrum emitted by the unknown celestial object in this situation.
The electromagnetic spectrum refers to the variety of frequencies (the spectrum) of electromagnetic radiation, as well as the wavelengths and photon energies associated with each frequency.
The goal of the electromagnetic spectrum experiment is to determine what elements are present in the atmospheres of the planets and moons by examining their absorption spectrums.
The electromagnetic spectrum encompasses electromagnetic waves with frequencies ranging from below one hertz to above 1025 hertz,
The frequency corresponds to wavelengths ranging from thousands of kilometers to a fraction of an atomic nucleus's size.
The electromagnetic waves within each frequency band are given various names, starting at the low frequency (long wavelength) end of the spectrum.
Hence the dependent variable is the one that changes as a result of the independent variable.
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