Green.
White light minus green light would appear as a purplish color. This is because when green light is removed from white light, the remaining color components combine to create a mix of blue and red light, which results in a purplish hue.
The red object would appear black because it would not reflect any of the green light shining on it. Green light is the complementary color of red, meaning the object would absorb all the green light and not reflect any color back to our eyes.
A lemon would appear green under green light because the object reflects the color of light that it does not absorb. In this case, a lemon's yellow color would absorb all other colors except green, which it would reflect.
yellow-green
A cucumber would appear green in green light, white in white light, and dark in red light as it would absorb most of the red light.
it would appear black.
Chlorophyll primarily reflects green light, which is why plants containing chlorophyll appear green to our eyes. This pigment absorbs light in the blue and red spectrum for photosynthesis, while reflecting green light.
To make green appear black, shine red light on it. Green absorbs red light, so when red light is shone on green, the green will appear black.
A green object under green light would appear its original color and shade of green. When an object is illuminated by light of the same color, no new colors are absorbed or reflected, resulting in the object appearing unchanged.
In red light, a green apple would appear dark or black because red light contains wavelengths that are opposite to green on the color spectrum. This causes green objects to absorb the red light and reflect very little, resulting in a dark appearance.
The green object will appear black because red light is absorbed by green objects.