Answer:
1. The type of interference happening when intersecting light waves subtract from each other to create dark spots is known as destructive interference
Destructive interference happens when the positive displacement or crest of one wave is cancelled by the negative displacement, or through of another wave of the same frequency resulting in a wave with lower amplitude
The letter on the diagram that shows destructive interference is the letter "c"
2. When particles pass translate through a key hole, they do not interfere with each. Therefore, when light is considered as a stream of particles, when it passes through a keyhole, there will be no interference, and the light will particles will not interact with other light particles such that the pattern formed on on a wall on the other where the particles impinge on will be the shape of the single slit or keyhole
3. Three behaviors of light that support the theory that light travels in waves includes;
a) Refraction
b) Interference
c) Diffraction
Refraction
Refraction describes the change in velocity of light when it travels from one medium to another of different density, in which the light changes its speed
Interference
Interference is the superposition of two or more waves with the addition of the wave displacements resulting in a wave of larger or lesser amplitude than each of the individual waves
Diffraction
Diffraction is defined as the tendency of light to bend or spread when it goes past an object placed in its path by passing around the objects edge
4. The properties of a blackbody radiator includes;
1) A blackbody radiator absorbs all electromagnetic radiation incident on it
2) A blackbody radiator is capable of emitting black-body radiation
3) The peak of the emitted radiation depends on the blackbody temperature
4) The length of the wavelength of the peak radiation is inversely proportional to the temperature of the blackbody
5) The blackbody has zero coefficient of reflection or transmission and therefore, it does not reflect incident heat or light which makes it black
An example of a blackbody radiator is a burglar alarm that flashes light when there is an incident but cannot be ordinarily seen because of its dark color which is meant to absorb all incoming light
Explanation:
Wave interference is the phenomenon which describes the effect of the coming together or superposition of two or more waves to result in a wave displacement at a given point that is either reinforced (larger), cancelled (lower) amplitudes or the waves may have their original amplitudes when there is no interference
The wave displacement for the waves coming from the same source are taken as vectors from which the combination is calculated by using vector addition.
