Question

Delay What is the required mass ratio to achieve an exhaust velocity of 2.455 km/s with a specific impulse of 294 seconds? Choose one. A. 2.34 B. 2.12 C.3.12 D.5.11 E. 4.33

Answer 1

Answer:

$\frac{mo}{mi} = 2.34$

Explanation:

Given data:

exhaust velocity = 2.455 km/s

specific impulse = 294 second

$\Delta V = Ve ln\frac{mo}{mi}$

$\Delta v = velocity$

Ve = effective exhaust velocity

$Ve = Isp\time s g_0$

Isp specific impulse

g_o = standard gravity

$vE = 294 \times 9.8 = 2881.2 m$

from above equation we have

$\frac{mo}{mi} = e^{\frac{\Delta v}{Ve} [tex]\frac{mo}{mi} = e^{\frac{2455}{2881.2}$       [ 2.455 km/s = 2455 m/s]

$\frac{mo}{mi} = 2.34$