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Wavelength from a graph

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For the hydrogen spectrum, how do you find the wavelength (experimental value in nm) from a graph? I don't understand what exactly you are plotting and how to get the wavelength from the graph. For example, if your scale readings are:

Violet-4.5, Blue-5.0, Yellow-6.0, Red-6.6

The same question applies to the spectra of cations when you have different solutions such as LiCl and your scale readings are:

Red-6.8, Yellow-6.1, Blue 4.6

How do you find these wavelengths from the graph?

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https://brainmass.com/chemistry/general-chemistry/wavelength-graph-16623

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Dear student,
Spectrum means power vs wavelength(or frequency). To make the graph simpler the indexes on 10 (e.g., 4.5*10^(-7) m ) are not shown in the graph, and it is ...

Solution Summary

This solution explains scales in graphs and how to find wavelengths using listed scales.

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2. A siren on top of a tower produces a sound whose power level is measured to be 68 dB at a distance 50 m from the tower.

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4. What is the period, in m/s of a sound whose frequency is 9800 Hz?

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6. You will need a whole page of graph paper for this one. Sketch a graph of a sine wave. Take up the entire width of the paper, displaying 2 complete cycles. The height of the wave should be 1 to 1.5 inches, as you wish. Now, on the same graph but using a dashed line, sketch another sine wave with the same frequency, but out of phase by 90°: the second wave should lag the first by 90°. (This means, for example, that a "zero" of the second wave occurs when the first wave has a value of 1.0.) Finally, sketch the sum of the two waves. (Use a different color or a heavier pen to tell the difference.) You don't have to do any arithmetic. Just add the vertical distances visually for several points and draw a smooth curve through your points.

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