Physics
When a fish has to rise up in water, it diffuses oxygen gas from its blood into the bladder, so its volume …………… and its average density …………… .
- decreases, decreases
- increases, decreases
- decreases, increases
- increases, increases
Answer
increases, decreases
Reason — When a fish has to rise up in water, it diffuses oxygen gas from its blood into the bladder, so its volume increases and its average density decreases
This increases the volume of water displaced by the fish and so the upthrust on the fish increases due to which it rises up.
Related Questions
Ice bergs float on the surface of water with their …………… portion inside the water surface and …………… portion above the water surface.
- smaller, larger
- larger, equal
- smaller, smaller
- larger, smaller
A balloon does not rise indefinitely because :
- the density of air increases with altitude
- the density of air decreases with altitude
- the weight of the displaced air increases.
- None of the above
State the principle of floatation.
When a piece of wood is suspended from the hook of a spring balance, it reads 70 gf. The wood is now lowered into water. What reading do you expect on the scale of spring balance?
[Hint: The piece of wood will float on water and while floating, apparent weight = 0].