11.

Zinc oxide is thermochromic, changing from white to yellow when heated to high temperature. This colour change is caused due to :

• Stoichiometric property of metal

• Non-stoichiometric property of metal

• Burning of oxygen

• Fluorescence at high temperature

A wild form animal gives one egg and mutant from gives three egg per year respectively. If all parents and progenies survive, then what would be the ration of number of wild to mutant after four years?

• 4

• 2 × 4

• 2 × 3 × 4

• 2⁴

Which of the following is responsible for ozone hole?

• CO₂

• CH₄

• Chlorine

• NO

Earth is active planet and have phenomenon like volcano, earthquake and continental drift. The major source for continental drift is:

• Moon gravity

• Earth gravity

• Radioactivity in core of earth

• Energy from sun

The mean salinity of sea 35 gm per liter. The main cause of this observed salinity is

• Evaporation and rainfall

• Photosynthesis

• Crust erosionand surface run off

• Rivers drainage

If the handle of a door placed at hinges is displaced toward center, more force is required to open it because:

• Less moment of force

• More moment of force

• Force will be zero

• Centre of gravity is zero

If a gas is released from pressurized bottle, then which statement will be true for release gas ?

• It will gain energy

• It will have same temperature as in bottle

• It will gain temperature

• It will cool as compare to gas in container

Which statment is not correct for all mammals?

• Absence of scales

• Absenceof laying egg

• Absence of segmentation

• Presence of asexual reproduction

Smog is due to

• Air pollution derived from smoke and vehicles

• More moisture in environment

• Increase in CO₂

• Low temperature of earth surface

Which of the following is not a direct consequence of greenhouse effect?

• Increase in sea level

• Rainfall

• Tsunami

• Global warming