Question

Why fishes survive in ponds even when the atmospheric temperature is well below 0 C.
ICSE Class 9 Physics Chapter Heat and Energy

Answer 1

1st of all... the freezing point of water is 0degree Celsius....... so when water reaches this temperature the upper layer of water starts freezing 1st ......
so in this way this outer layer which is frozen acts as a shield and doesn't allow the rest water (beneath it) to freeze.... and hence the temperature of rest layers are a bit high .....
so fishes can survive even at 0 Celsius....

moreover if we look biologically ... we will find that such organisms have more amount of brown fat.... may be in the form of blubber which acts as insulator and prevents heat loss from their body....

For Information :
brown fat are those fat which produces only heat and not energy....

hope it helps you.......
:)....