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

• the lift is going up with uniform speed

• the lift is going down with an acceleration

• the lift is going down with uniform speed

• the lift is going up with an acceleration

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 

Which of the following is used in pencils?

The branch of medicine involving synthetic chemical compounds is