The phenomenon we are seeing is called additive and subtractive color mixing. When blue, green, and red light combine, they create white light due to additive mixing. However, when you use a slit to block parts of this combined white light, you’re engaging in subtractive color mixing. The slit essentially acts as a filter, allowing only certain wavelengths of light to pass through. Shadows cast by objects result from the selective absorption of certain wavelengths of light, producing three disti