B Discovering the Correct Rocket Mass Ratio for Beginners

[Dr Wu]

I'd always thought that to find the mass ratio of a given rocket, one simply had to divide the rocket's wet mass (i.e. fuel and propellant) from its total mass. An example: a rocket's total mass = 2,000 tonnes: its wet mass = 1,000 tonnes. Answer: 2. Is this correct? (I'm pretty sure it isn't, but I can't see where I'm going wrong).

PS. More realistically, if the wet mass of a rocket is 2,000 tonnes, and its dry mass is 200 tonnes, does this mean the mass ratio is 10? If so, we're talking about a total mass of 2,200 tonnes. . . right?

 

[mfb]

The wet mass is the total mass.

The mass ratio is simply wet mass divided by dry mass.