Question 1: Light is a form of electromagnetic radiation that is visible to the human eye. The colour of an object depends on the way it interacts with light, particularly how it absorbs, reflects, or transmits different wavelengths. Understanding colour involves exploring how objects appear in various lighting conditions and how our eyes perceive these differences.

Answer: Light consists of electromagnetic waves visible to humans, and an object's colour depends on which wavelengths it reflects or transmits to our eyes.

Question 1: Define the term 'spectral colour'.

Answer: A spectral colour is a colour that corresponds to a single wavelength of light in the visible spectrum.

Question 2: Explain why a red apple appears red under white light.

Answer: The apple appears red because it reflects red wavelengths of light and absorbs other colours.

Question 3: Which part of the electromagnetic spectrum is responsible for colour perception in humans?

Answer: Visible

Question 4: Fill in the blank: Objects that appear white reflect ____ wavelengths of light equally across the visible spectrum.

Answer: all

Question 1: Describe the process by which a blue object appears blue to our eyes.

Answer: A blue object appears blue because it reflects blue wavelengths and absorbs other colours.

Question 2: What is colour subtraction, and how does it relate to mixing paints?

Answer: Colour subtraction involves the removal of certain wavelengths of light through absorption. When mixing paints, the colours combine by subtracting certain wavelengths, resulting in a new colour seen by the observer.

Question 1: Identify the variables that affect the colour appearance of a car's paint in different lighting conditions.

Answer: Lighting conditions, angle of viewing, surface finish, and type of light source.

Question 2: State two safety precautions when performing experiments involving coloured light filters.

Answer: Avoid direct exposure to intense light sources and handle filters carefully to prevent scratches or damage.

Question 3: Explain how colour filters are used in photography to alter the appearance of images.

Answer: Colour filters in photography absorb certain wavelengths of light, allowing only specific colours to pass through. This alters the colour balance of the image, enhancing or reducing certain hues.

Question 1: A piece of fabric appears green under daylight but looks black under a red light. Explain why this occurs.

Answer: The fabric reflects green light but absorbs red light. Under red light, it reflects very little, appearing black.

Question 2: Describe how understanding colour in light is important in the design of LED displays and screens.

Answer: Designers use knowledge of how different wavelengths combine to produce various colours in LED displays. Understanding colour mixing, emission spectra, and human visual perception allows for the creation of vibrant, accurate screens.

Question 1: In your own words, explain why objects have different colours and how this relates to the light they interact with.

Answer: Objects have different colours because they absorb, reflect, or transmit specific wavelengths of light. The colour we see is the combination of wavelengths reflected or transmitted to our eyes. This interaction depends on the object’s material and the light source, which determines how the object appears in different environments.