How do different types of light affect plant growth?

Grade:

9

Teacher:

Ranbir Gill

In this experiment, we tested the effect of different light sources—sunlight, red LED light, and lamp light—on the growth of lettuce, radish, and bean seeds. Our hypothesis was that sunlight would produce the best growth. The results showed that lettuce seeds grew best in sunlight, reaching 7 cm by the third week. Under red LED and lamp light, lettuce grew to 6 cm and 5.5 cm respectively by week three. However, the radish and bean seeds did not grow at all under any light condition, which limited our data and comparison. Despite this, the results clearly demonstrate that sunlight was the most effective light source for growing lettuce in our experiment.

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