The centre of gravity and the centre of buoyancy of a floating body in stable equilibrium(i) are always same(ii) are always along a same vertical line
only (i) is true
only (ii) is true
Both (i) and (ii) are correct
Both (i) and (ii) are false
Relative density of silver is 10.8. Calculate its density in the SI units.
10.8 kgm-3
10800 kgm-3
1.08 kgm-3
1080 kgm-3
A piece of pure gold ( = 19.3 gcm-3 ) is suspected to be hollow from inside. It weighs 77.2 g in air and 71.2 g in water.The volume of the hollow portion in gold will be
3 cm3
1 cm3
2 cm3
4 cm3
What is the density of water?
1000 g cm-3
1 g cm-3
1 kg m-3
none of these
A combination of wood and iron, just floats in the water at room temperature. Explain what you will observe when the water is heated.
The combination will still float with same position.
The combination will float on the surface of the liquid.
The combination will sink.
None of the above.
For what purpose is the acid battery hydrometer used?
To find the density of hydrochloric acid in an acid battery
To find the relative density of sulphuric acid in an acid battery
To find the density of sulphuric acid in an acid battery
To find the relative density of hydrochloric acid in an acid battery
Relative density of a substance is expressed by comparing the density of that substance with the density of
Mercury
Air
Water
Iron
In case of hydrometer for lighter liquids
its gravity bulb is heavier
the densities of lighter liquids are marked below the density of water.
the density of water is marked at the top of stem.
Its buoyancy bulb is larger
A substance floats in water, but sinks in coconut oil. The density of the substance
is less than the density of water and equal to the density of oil
is greater than the density of oil and equal to the density of water
is less than the density of water and greater than the density of oil
cannot be decided based on the given information.
The narrow stem in a hydrometer.
increases its size.
increases upthrust on it.
raises its centre of gravity.
increases its sensitivity.
