User:Milton Beychok/Sandbox: Difference between revisions
Jump to navigation
Jump to search
imported>Milton Beychok |
imported>Milton Beychok |
||
Line 13: | Line 13: | ||
:<math>I = F \Delta T = \int {F dt} = \int {\dot {m} V_{eq}\, dt} = \dot {m} V_{eq}</math> | :<math>I = F \Delta T = \int {F dt} = \int {\dot {m} V_{eq}\, dt} = \dot {m} V_{eq}</math> | ||
The specific impulse ( '''''I<sub>sp</sub>''''' ) is the total impulse divided by the [[weight]] of the exhaust gas: | |||
:<math>I_{sp} = I/\text {weight} = \frac {I}{\dot {m} g_o} = \frac {F}{\dot {m} g_o} </math> | |||
{{reflist}} | {{reflist}} |
Revision as of 16:31, 24 March 2010
Rocket thrust and specific impulse
Thrust is the force (F) which moves a rocket through the air. Thrust is generated by the rocket engine through the reaction of accelerating a mass of gas. The gas is accelerated to the the rear and the rocket is accelerated in the opposite direction. Force may be mathematically expressed as:[1][2]
and also this form, by defining a new term veq :
The total impulse of a rocket is defined as the average thrust multiplied by the total time of propellant burning:
The specific impulse ( Isp ) is the total impulse divided by the weight of the exhaust gas:
- ↑ Rocket Thrust Summary from a website page of the National Aeronautics and Space Administration (NASA)
- ↑ Specific Impulse from a website page of the National Aeronautics and Space Administration (NASA)