So, you can get the mass of a flat object with density.

因此，可以通过密度求一个平面物体的质量。

youdao

We knew the density of steel, and so you can figure out the mass, just take my word for it.

我们知道铁的密度，所以你能算出质量，相信我说的。

youdao

The gap between them will change as the ships pass over regions of higher and lower mass, providing clues to the density of the subsurface moon.

两个飞行器间的距离会随着飞船经过的区域的密度高低的变化而改变，为月球表面的密度提供线索。

youdao

But accurately working out Mathilde's volume (necessary because density is the ratio of mass to volume) was harder.

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He studies the material properties of tissue and organs from animals and cadavers to assign shape, size, density, mass and ten or more coefficients that describe how each cube of virtual flesh will deform when confronted with a given force from a given direction.

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