Science Quiz

What does Dry powder form of chemicals release to extinguish fire?

• Soot

• Carbon monoxide

• Carbon dioxide

• Carbon trichloride

Why does the flame always point upwards?

• Gases produced during combustion are lighter than air

• Gases produces during combustion are heavier than air

• The flame pointing upward does matter if gas released is lighter or heavier

Inflammable substances have __________ ignition temperature

• high

• moderate

• Extremely high

• low

In reverse osmosis water is forced out through a ____________

• hard membrane

• semi-permeable membrane

• permeable membrane

• Impermeable membrane

Charcoal helps in _____________ of impurities

• Absorbtion

• Absorption

• Desorption

• Adsorption

Chemical treatment is done by which of the following:

answer choices

• chlorine

• Potassium permanganate

• charcoal

• ozone

• Bleaching powder

What principle does Maglev train work on?

• Friction

• Repulsion between magnets

• Attraction between magnets

• All of the above

A rocket has been fired up to launch a satellite in its orbit. Name the two forces acting on the rocket immediately after leaving the launch pad.

• Muscular force

• Gravitational force

• Frictional Force

• Magnetic force

• Electromagnetic force

Name the lubricant which is used in machinery where oil cannot be applied

• fatty alcohols

• Graphite

• Grease

• water

• only oil can be used

What is produced when there is a photochemical reaction of sunlight with hydrocarbons and nitrogen oxides?

• fog

• Dust and residue

• smoke

• Smog