1. What is the measure of a) angle of incidence and b) angle of refraction when a Ray of light is incident normal to the separating surface?
2. Mention 2 differences between boiling and evaporation.
3. Mention 2 conditions for work to be done.
4. Calculate the amount of work done when a force of 25 N displaces a body through 5 metre .
5. Mention the two factors on which kinetic energy depends.
6. Define the term power . Mention the SI unit of power.
7. Mention two industrial uses of ultrasonic vibrations.
8. Define the term time period. How is it related to frequency?
Answers
Answer:
When light passes from one medium to another with different densities, its path gets deviated. This phenomenon is called the refraction of light. Like a reflection, there are similar components in refraction too. They are:
Incident ray
Refracted ray
Normal
Point of incidence
The angle formed at the point of incidence between the incident ray and the normal is called the angle of incidence. The angle formed between the refracted ray and the normal is called the angle of refraction.
Angle of Incidence and Angle of Refraction
The relationship between the angle of incidence and angle of refraction is explained by Snell’s law, which states that the ratio of the sine of the angle of refraction and the sine of the angle of incidence is always constant and equivalent to the ratio of phase velocities of the two mediums it is passing through.