What color light will a red object appear when viewed through a green filter?

When a red object is viewed through a green filter, it will appear black. This is because a filter allows only certain wavelengths of light to pass through while blocking others. A green filter transmits green light and absorbs other colors, including red. Since the red object reflects red light, when this red light passes through a green filter, it cannot reach the observer's eye because the filter does not transmit it. As a result, the object will appear black, indicating that there is no light being reflected back to the viewer from the object in the presence of the green filter.