“mass ratio”的概念、定义、翻译、参考文献-科学参考

mass ratio

Astronomy

An expression of the relative masses of the components of a binary star when both spectra are visible. It is derived from the radial velocity curves for both components and may be written as M₂/M₁ = a₁sin i/a₂ sin i, where M₁ and M₂ are the masses of the components, and a₁ and a₂ are the amplitudes of the velocity curves. If the orbital inclination, i, can be determined (as in an eclipsing binary) the actual masses of the components, and the dimensions of the stars and their orbits, can be obtained.

Space Exploration

The mass of a vehicle (usually a rocket) at lift-off, divided by the mass of the empty vehicle without propellants. Mass ratio is often used as an indicator of a rocket's performance. The greater the mass ratio, the more propellant the rocket can carry, resulting in a better lifting performance from the vehicle. The ratio can be increased by the use of more lightweight materials on the rocket and improvements to the method of introducing the propellants to the combustion chamber. The choice of propellants is also a factor: some are much heavier than others. Typical mass ratios range from 5:1 for boosters using pressure-fed liquid hydrogen propellant, to 17:1 for pumped hydrogen peroxide.

单词	mass ratio
释义	mass ratio Astronomy An expression of the relative masses of the components of a binary star when both spectra are visible. It is derived from the radial velocity curves for both components and may be written as M₂/M₁ = a₁sin i/a₂ sin i, where M₁ and M₂ are the masses of the components, and a₁ and a₂ are the amplitudes of the velocity curves. If the orbital inclination, i, can be determined (as in an eclipsing binary) the actual masses of the components, and the dimensions of the stars and their orbits, can be obtained. Space Exploration The mass of a vehicle (usually a rocket) at lift-off, divided by the mass of the empty vehicle without propellants. Mass ratio is often used as an indicator of a rocket's performance. The greater the mass ratio, the more propellant the rocket can carry, resulting in a better lifting performance from the vehicle. The ratio can be increased by the use of more lightweight materials on the rocket and improvements to the method of introducing the propellants to the combustion chamber. The choice of propellants is also a factor: some are much heavier than others. Typical mass ratios range from 5:1 for boosters using pressure-fed liquid hydrogen propellant, to 17:1 for pumped hydrogen peroxide.
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