How To Make RGB WALL LIGHT

How many kilometres make 1 light year ?

How make light years are there in one metre?

How is refracted most by a prism : red light or violet light ? Explain why ?

A ladder 15m long makes an angle of 60^(@) with the wall. Find the height of the point , where the ladder touches the wall.

Figure shows a torch sending a parallel beam of light fixed on a wall and a plane mirror which forms a spot on the wall. As the mirror moves towards the wall, the spot on the wall moves

How many lakhs make a million? How many lakhs make a billion?