Click on the objects to find out and learn about light.

How non-luminous objects are seen Light is produced by luminous objects, like the lamp, travels in a straight line and then scatters off the non-luminous object, which is the teddy bear and straight into a the eye(s) of the person detecting it. Rules to use when drawing ray diagrams 1.Use a pencil and ruler 2.Make sure that the ray of light is emitted from the part of the luminous object that produces light. 3.Make sure that the ray of light is continuous with no gaps in it. 4.Make sure that the ray of light enters the eye.

Reflection of Light The angle of incidence equals the angle of reflection

Refraction of Light When light travels into or out of a medium that is more or less dense the light will bend or refract.

White Light and colour White light is made up of 7 different colours. They appear in a rainbow when they are dispersed and can be seen in the following order: Red Orange Yellow Green Blue Indigo Violet The 7 colours that make up white light can be dispersed, which means separated, using a glass, triangular prism. The different light colours refract by different amounts when they enter into the prism. The red light refracts the least and the violet light the most.

Key Vocabulary and Glossary – Light Angle of incidence – An angle that is created between the incident ray and the normal. Angle of reflection – An angle that is created between the reflected ray and the normal. Density – A measurement of how close the particles in a medium are together or a measurement of how heavy something is for its size. Emitted – To give out light. Incident ray – A ray of light that is produced by a luminous object. Light – A form of energy that travels in transverse waves. Luminous object – An object that produces light. Medium – Something that contains particles. Normal line – An imaginary line that is formed perpendicular (90 0 from surface of object) from the point in which a ray of light hits a surface. Reflected ray – A ray of light that is reflected off a plane mirror. Reflection – When light bounces off a surface. Refraction – the bending of light. Transmitted – to pass into something.

Why objects have a colour Yellow objects All the colours in white light are absorbed into the yellow object apart from yellow light, which is reflected to the eye. This is what makes the object yellow Red objects All the colours in white light are absorbed into the red object apart from red light, which is reflected to the eye. Blue objects All the colours in white light are absorbed into the blue object apart from blue light, which is reflected to the eye.

Why objects have a colour White objects White objects reflect all of the colours in white light. All these colours combine to make white, which is why white objects have this colour. Black objects Black objects absorb all of the colours in white light. No light reflects off black objects, which is why they a detected as being black. Black is not a colour of light it is an absents of light.

Why objects have a colour What colour would a green object look in red light? Click here to find out. What colour would a white object look in green light? Click here to find out.

Why objects have a colour White objects reflect all colours of light. As there is only green light shinning on the white brick it will look green. This is the only colour that is reflected to the eye.

Why objects have a colour All the red light would be absorbed into the green object. No light would reach the eye making it look black.