Questions

Caffeine is also a psychoactive drug which alters the mood and conscious in our behaviour. It is widely consumed as a psychoactive drug.

p type of semiconductor is obtained when Silicon is doped with a trivalent impurity like Aluminium. Aluminium is a p-type dopant, which means that when a semiconductor i.e. silicon is doped with aluminium, it creates a hole (positively charged carrier) by accepting an electron from the silicon atom. Electrical conductivity of semiconductors increasesand resistivity remains the same

I am black gold i.e charcoal. It is black when it is not used and when using it is red due to fire and when used it is in grey color as it becomes ash. 

without this centripetal force, circular motion is not possible. It acts radially towards the centre and if this force is removed there will be no circular motion but the revolving body will fly off at a tangent.

A Dice has 6 faces with 1 - 6 number of dots one on each side.

So in total 1 + 2 + 3 + 4 + 5 + 6 = 21 dots resembles as eyes.

Sublimation is a process when a solid changes directly into gas instead changing into liquid first. Dry ice is an example of Sublimation process because it doesn't change into liquid CO2 and directly change into gaseous CO2 when heated.

Hence, Dry ice is an example of Sublimation process.