Question

In multi-stage rockets, the stage mass fraction is defined as

• A. Ratio of payload mass to total rocket mass
• B. Ratio of propellant mass to total stage mass
• C. Ratio of total rocket mass to payload mass
• D. Ratio of dry mass to payload mass

Hint:

For a rocket stage, \[ \boxed{ \text{Mass Fraction} = \frac{m_p}{m_{\text{stage}}}, } \] where \[ m_{\text{stage}} = m_p+m_s, \] \(m_p\) is propellant mass and \(m_s\) is structural mass.

Answer 1

The Correct Option is B

Step 1: Recall the definition of stage mass fraction. The stage mass fraction is defined as \[ \boxed{ \text{Stage Mass Fraction} = \frac{\text{Propellant Mass}} {\text{Total Stage Mass}}. } \] The total stage mass includes both the propellant and the structural mass of that stage.

Step 2: Identify the correct option. Hence, \[ \boxed{ \text{Stage mass fraction} = \frac{\text{Propellant Mass}} {\text{Total Stage Mass}}. } \] Therefore, \[ \boxed{(B)} \] is the correct answer.