We have a fully filled glass jar with 1 kg of mercury. If you empty the jar, you can put 1 kg of water in it?

We have a fully filled glass jar with 1 kg of mercury. If you empty the jar, you can put 1 kg of water in it?


Solution

The volume represents how much space a substance in our case occupies in m³ (cubic meters).

We calculate the volume for each substance based on density and find out if the volume occupied by 1 kg of mercury is the same as the volume occupied by 1 kg of water.



We use the substance density formula:

ρ = m / V

we know the density for each substance from the table with densities and the mass that is 1 kg and we find the volume for each of them:


V = m / ρ


The volume occupied by 1 kg of mercury:

V = 1kg / ρ

V = 1kg / 13.600 kg / m³

Vmercury = 0,000074 m³



The volume occupied by 1 kg of water:

V = 1kg / ρ

V = 1 kg / 1000 kg / m³

Vwater = 0.0001 m³



Vwater > Vmercury


So, 1 Kg of water occupies more space than 1 kg of mercury.

In our case 1 kg of water will not enter in the jar in which was 1 kg of mercury.



Legend

m = mass (kg)

V = volume (m³)

ρ = density (kg / m³)


Mechanics

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