Question
How do fishes survive in frozen lakes?
✓
Answer
Fishes survive in pond even when the atmospheric temperature is below $0^{\circ} C$. It is because of anomalous expansion of water. When the temperature falls below $0^{\circ} C$ water changes into ice and rises to the top and ice being poor conductor of heat helps to keep water below it at $4^{\circ} C$ and fish can live in pond water.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.
Explore more
Similar questions
A body starts from rest with uniform acceleration $2 m s ^{-2}$. Find the distance covered by the body in 2 s .
→Complete the following diagram of magnets to show the lines of force.
Does light travel faster in air than in water? Why?
What is meant by the term retardation? Name its S.I. unit.
State the positions of neutral points when a magnet is placed with its axis in the magnetic meridian and with its north pole (i) pointing towards the geographic north and (ii) pointing towards the geographic south.
An body is dropped from the top of a tower. It acquires a velocity $20 m s ^{-1}$ on reaching the ground. Calculate the height of the tower. (Take $g =10 m s ^{-2}$ )
→Define the term Principal focus.
Distinguish between uniformly and non-uniformly accelerated motions.
Give four reasons, why the use of cowdung in biogas preferred to burning of cowdung cakes.
A person is listening to a tone of 500 Hz sitting at a distance of 450 m from the source of the sound. What is the time interval between successive compressions from the source?