A red flower seen in the light of mercury vapour lamp through a green filter wil appear in what colour?
To determine the color of a red flower seen through a green filter in the light of a mercury vapor lamp, we need to consider the properties of the object (the flower), the light source (the mercury vapor lamp), and the filter (green).
The color of an object is determined by the wavelengths of light it reflects. For example, a red flower appears red because it reflects predominantly red light while absorbing other colors.
A green filter allows green light to pass through while absorbing other colors. So, when we view a red object (like a flower) through a green filter, the filter will absorb most of the red light and allow only green light to pass through to our eyes.
Now, let's consider the light emitted by a mercury vapor lamp. Mercury vapor lamps emit light in a characteristic spectrum, which includes distinct lines of different colors, such as blue, green, and yellow.
Based on this information, when we view a red flower through a green filter in the light of a mercury vapor lamp, the flower will appear dark or black. This is because the flower's red light will be mostly absorbed by the green filter, and the lamp's characteristic green light will not be reflected by the flower. Instead, the flower will appear to be in shadow or dark due to the absence of reflected or transmitted light.
In summary, a red flower seen through a green filter in the light of a mercury vapor lamp will appear dark or black.