Physics - Study Mode

[#751] Electrical Energy is the energy of
Correct Answer

(C) Electrons

Explanation

Solution: The SI unit of resistance is electrons.

[#752] As water is cooled from 4 deg C to 0 deg C, its density
Correct Answer

(B) Decreases

Explanation

Solution: When water is cooled from 4°C to 0°C, its density decreases.

[#753] Fish and other aquatic creatures can live inside a deep frozen pond because
Correct Answer

(C) There will always be water just beneath the ice level

Explanation

Solution: All liquids have a boiling point and a freezing point. Underneath the frozen upper layer, the water remains in its liquid form and does not freeze. Also, oxygen is trapped beneath the layer of ice. As a result, fish and other aquatic animals find it possible to live comfortably in the frozen lakes and ponds.

[#754] The density of a gas is maximum at
Correct Answer

(B) Low temperature, high pressure

Explanation

Solution: The density of gases depends upon the temperature. The higher the temperature, the more the molecules are spread out and the lower the density.

[#755] Lakes freeze in cold countries in winter, leaving the water underneath at
Correct Answer

(C) 4°C

Explanation

Solution: Freezing takes place at he top of the lake this is because water colder than 4 degree celsius usually starts to expand and get less dense as it gets colder. It is the liquid with more density that settles at the bottom while the less denser floats above it.