Rainbows are produced by when sunlight 

• incident on rain drops hanging in the atmosphere is dispersed after suffering refraction

• incident on rain drops hanging in the atmosphere is dispersed after suffering reflection

• incident on rain drops hanging in the atmosphere is dispersed after suffering refraction and internal reflection

• None of the given statements is correct

The blue revolution is related with 

The purpose of choke in a fluorescent lamp is

The apparent weight of a man in a lift is less than the real weight when

Addition of excessive amounts of heat to lake is referred to as

The mercury and sodium street lamps light up because of

From the national point of view which of the following indicates Micro Approach?

Competition for food, light and space is most severe in

The green colour seen in firework displays is due to the chloride salt of

Kautilya's 'Artharshastra' mainly deals with

Rainbows are produced by when sunlight