that the wavelength or energy was near 254 nm, which is the maximum absorption rate of . Photons from UV light create dimers in the that break the chemical bonds and prevent replication which leads to the death of the cells (Aguiar et al.). The longer the E. coli was exposed to the ultraviolet light, the more cells lost the ability to replicate because more dimers are created. SAVE FOR CONCLUSION Figure 11. Effect of Distance from the UV Light Figure 11 and Table 7 above show that on average, as the distance from the UV light increased, the number of E. coli colonies decreased by approximately 112 colonies. Figure 11 shows that as the distance from the UV light became Distance from the UV (cm) (-) (+) closer, the number of E. coli colonies decreased. This 171.266667 86.9333333 230.733333 91.5333333 means that as the distance from the ultraviolet light to Avg = 201 Avg = 89.2333333 the Petri dish increased from 24 cm away to directly in front of the UV light the amount of E. coli colonies on average decreased by about 112 colonies. The reason behind this is that more photons are absorbed when the E. coli is closer to the light source, which create dimers and prevent replication. This is a much larger effect than the effect of duration because the number of photons drastically decreases as the distance increases in accordance to the inverse square law (“Inverse Square Law”). SAVE FOR CONCLUSION Distance (-) (+)
that the wavelength or energy was near 254 nm, which is the maximum absorption rate of . Photons from UV light create dimers in the that break the chemical bonds and prevent replication which leads to the death of the cells (Aguiar et al.). The longer the E. coli was exposed to the ultraviolet light, the more cells lost the ability to replicate because more dimers are created. SAVE FOR CONCLUSION Distance from the UV (cm) (-) (+) 171.266667 86.9333333 230.733333 91.5333333 Avg = 201 Avg = 89.2333333 Figure 11. Effect of Distance from the UV Light Figure 11 and Table 7 above show that on average, as the distance from the UV light increased, the number of E. coli colonies decreased by approximately 112 colonies. Figure 11 shows that as the distance from the UV light became closer, the number of E. coli colonies decreased. This means that as the distance from the ultraviolet light to the Petri dish increased from 24 cm away to directly in front of the UV light the amount of E. coli colonies on average decreased by about 112 colonies. The reason behind this is that more photons are absorbed when the E. coli is closer to the light source, which create dimers and prevent replication. This is a much larger effect than the effect of duration because the number of photons drastically decreases as the distance increases in accordance to the inverse square law (“Inverse Square Law”). SAVE FOR CONCLUSION Distance (-) (+)
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