Advertisements
Advertisements
प्रश्न
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?
उत्तर
The reading on the spring balance will be zero because wood floats on water and while floating the apparent weight = 0.
APPEARS IN
संबंधित प्रश्न
For a floating body, its weight W and upthrust FB on it are related as :
A body floats in a liquid A of density ρ1 with a part of it submerged inside the liquid, while in liquid B of density ρ2 it is totally submerged inside the liquid. The densities ρ1 and ρ2 are related as :
A weather forecasting plastic balloon of volume 15 m3 contains hydrogen of density 0.09 kg m-3. The volume of equipment carried by the balloon is negligible compared to its own volume. The mass of an empty balloon alone is 7.15 kg. The balloon is floating in air of density of 1.3 kg m-3. Calculate:
(i) The mass of hydrogen in the balloon,
(ii) The mass of hydrogen and balloon,
(iii) The total mass of hydrogen, balloon and equipment if the mass of equipment is x kg,
(iv) The mass of air displaced by balloon and
(v) The mass of equipment using the law of floatation.
A hollow metal cylinder of length 10 cm floats in alcohol of density 0.80 g cm-3, with 1 cm of its length above it. What length of cylinder will be above copper sulphate solution of density 1.25 g cm-3?
A test tube weighing 17 gf, floats in alcohol to the level P. When the test tube is made to float in water to the level P, 3 gf of the lead shots are added in it. find the R.D. of alcohol.
Name an instrument based on this principle. State two uses of the instrument that you describe.
Explain the following:
An egg sinks in fresh water but floats in a strong solution of salt.
How does an object’s density determine whether the object will sink or float in water?
If you put one ice cube in a glass of water and another in a glass of alcohol, what would you observe? Explain your observations.
Why do petroleum-based products float on the surface of the water?
