Advertisements
Advertisements
Question
Higher Order Thinking Skill.
How does a fish manage to rise up and move down in water?
Advertisements
Solution
Fish has an internal swim bladder which is filled with gas. When it needs to rise or descend, it changes the volume and its density by filling this bladder with oxygen collected from the surrounding water through gills. When the bladder is filled with oxygen gas, the fish has a greater volume, with minimal increase in weight. When the bladder is expanded, it displaces more water and so experiences a greater force of buoyancy.
When the bladder is completely inflated, the fish has maximum volume and is pushed to the surface. When the bladder is completely deflated, the fish has minimum volume and sinks to the ocean floor.
APPEARS IN
RELATED QUESTIONS
The density of a body which sinks in water is ......... than 1000 Kg m-3.
The density of aluminium is 2.7 g cm-3 and that of brass 8.4 g cm’3. The correct statement is
Explain the following statement:
Sleepers are laid below the rails.
Write an expression for the pressure at a point inside a liquid. Explain the meaning of the symbols used.
Why do sea divers need special protective suit?
Complete the following sentence :
Pressure is .................... in all directions about a point in a liquid.
A simple U tube contains mercury to the same level in both of its arms. If water is poured to a height of 13.6 cm in one arm, how much will be the rise in mercury level in the other arm?
Given : density of mercury = 13.6 x 103 kg m-3 and density of water = 103 kg m-3.
Why is a force needed to keep a block of wood inside water?
A body of mass 3.5 kg displaces 1000 cm3 of water when fully immersed inside it. Calculate:
- the volume of body,
- the upthrust on body and
- the apparent weight of body in water.
Define atmospheric pressure diving suits. Does a diving suit create buoyancy?
