The density (more precisely, the volumetric mass density; also known as specific mass), of a substance is its mass per unit volume. The symbol most often used for density is ρ (the lower case Greek letter rho), although the Latin letter D can also be used. Mathematically, density is defined as mass divided by volume:
ρ
=
m
V
{\displaystyle \rho ={\frac {m}{V}}}
where ρ is the density, m is the mass, and V is the volume. In some cases (for instance, in the United States oil and gas industry), density is loosely defined as its weight per unit volume, although this is scientifically inaccurate – this quantity is more specifically called specific weight.
For a pure substance the density has the same numerical value as its mass concentration.
Different materials usually have different densities, and density may be relevant to buoyancy, purity and packaging. Osmium and iridium are the densest known elements at standard conditions for temperature and pressure.
To simplify comparisons of density across different systems of units, it is sometimes replaced by the dimensionless quantity "relative density" or "specific gravity", i.e. the ratio of the density of the material to that of a standard material, usually water. Thus a relative density less than one relative to water means that the substance floats in water.
The density of a material varies with temperature and pressure. This variation is typically small for solids and liquids but much greater for gases. Increasing the pressure on an object decreases the volume of the object and thus increases its density. Increasing the temperature of a substance (with a few exceptions) decreases its density by increasing its volume. In most materials, heating the bottom of a fluid results in convection of the heat from the bottom to the top, due to the decrease in the density of the heated fluid. This causes it to rise relative to more dense unheated material.
The reciprocal of the density of a substance is occasionally called its specific volume, a term sometimes used in thermodynamics. Density is an intensive property in that increasing the amount of a substance does not increase its density; rather it increases its mass.
The density of ice is 920 kg/m3.
Now let's calculate.
m = 269 000 000 000 000 kg
p = 920 kg/m3
-----------------------------
v=?
V=m/p
V=269 000 000 000 000 kg / 920 kg/m3
V = 292 391 304 347 m3 = 292 391 304.347 km3
v > 269 km3
*NOTE* I made a mistake in the title. I meant to write 269 km3...
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Homework Statement
Homework Equations
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Homework Statement
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Homework Statement
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Homework Statement
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Homework Equations
ΔL = FL/AY
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Homework Equations
F(Gravity) = ((GravitationalConstant)(Mass1)(Mass2))/radius^2
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Homework Statement
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Homework Statement
Homework EquationsThe Attempt at a Solution
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Homework Statement
Homework EquationsThe Attempt at a Solution
I fount these
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Part (b)
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Part (c)
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Homework Statement
Write the density operator
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In matrix form
Homework Equations
$$\rho=\sum_i p_i |\psi><\psi|$$
The Attempt at a Solution
[/B]
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Homework Statement
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Homework Statement
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Homework Equations...
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Homework Statement
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Homework Statement
Homework EquationsThe Attempt at a Solution
I have the full solution, the first part being:
I don't understand how they came up with the expression for Vab. I know usually ΔV=-∫E dl, but I'm not sure how they found their expression. Can someone explain? Thanks.