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Checking Two Emission Lines With a Finer Scan 4 questions
Checking Two Emission Lines With a Finer Scan
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A display tests gases with known emission-line models. Each line corresponds to a photon emitted during an electron transition. The coarse scanner merges two equal-strength lines if their wavelengths are less than 3 nm apart. It displays their average wavelength in that case. The fine scanner separates lines that are at least 1 nm apart.
| Gas model | Actual emission wavelengths (nm) |
|---|---|
| P | 590 |
| Q | 589 and 591 |
| R | 585 and 595 |
Question 1
Which gas models could each give a single coarse reading of 590 nm?
- P and Q
- P and R
- Q and R
- R only
Question 2
Explain why averaging the two wavelengths for R would give the wrong prediction for the coarse scan.
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The unknown gas gives a single coarse reading of 590 nm. Its fine scan shows two lines separated by 2 nm.
Question 3
Identify which model fits both scans. Explain why the single coarse reading was insufficient.
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Question 4
A student says the Q gas must emit a photon at 590 nm because that number appears on the coarse display. Evaluate the claim using the actual line model.
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