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Comparing Dye Changes After Light Pulses 4 questions
Comparing Dye Changes After Light Pulses
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A class models the fading of a dye under light. Three equal samples start with a color reading of 100 units. The same wavelength reaches each sample. During each pulse the power stays constant. A power of 1 mW delivers 1 mJ of energy per second.
| Trial | Power during pulse (mW) | Pulse duration (s) | Color reading after pulse |
|---|---|---|---|
| J | 2.0 | 3.0 | 80 |
| K | 6.0 | 1.0 | 80 |
| L | 2.0 | 6.0 | 65 |
Question 1
Which two trials deliver equal light energy at different powers?
- J and K
- J and L
- K and L
- All three trials
Question 2
Calculate the light energy delivered in L. Show how the duration affects the result.
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The students want to know whether peak power alone can explain the color readings. In each trial the listed power is the highest power during the pulse.
Question 3
Use J and L to evaluate the idea that the same peak power always gives the same final color reading.
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Question 4
Describe a second equal-energy comparison that would test whether the result for J and K also holds at a different total energy.
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