Physics
Light travels a distance of ‘10x’ units in time ‘t1’ in vacuum and it travels a distance of ‘x’ units in time ‘t2’ in a denser medium. Using this information answer the question that follows :
(a) ‘Light covers a distance of ‘20x’ units in time ‘t1’ in diamond.’ State true or false.
(b) Calculate the refractive index of the medium in terms of ‘t1’ and ‘t2’.
Related Questions
(a) Why do we use red colour as a danger signal on the top of a skyscraper?
(b) The diagram below shows the path of a blue ray through the prism :

- Calculate the critical angle of the material of the prism for blue colour.
- What is the measure of the angle of this prism (A)?
- Which colour should replace the blue ray, for the ray to undergo Total Internal Reflection?
A monochromatic ray of light is incident on an equilateral prism placed at minimum deviation position with an angle of incidence 45° as shown in the diagram.

(a) Copy the diagram and complete the path of the ray PQ.
(b) State two factors on which the angle of deviation depends.
(a) Define Centre of Gravity.
(b) A hollow ice cream cone has height 6 cm.
- Where is the position of its centre of gravity from the broad base?
- Will its position change when it is filled completely with honey? Write Yes or No.