Pleeeease help me. I have to do a twenty minute presentation on momentum changes in variable mass systems. I have everything done but examples. The equation I have is m(t)a=Rv where R is the rate the mass of the rocket is decreasing and v is the velocity of the gas ejected with respect to the rocket. Does anyone have any examples from the internet I can use? At least any realistic variables? I have absolutely NO idea what realistic numbers would be for this situation. Actually, to be honest, I'm not really sure how to use the equation. What would I have to have to solve for a sample? The velocity of the particles ejected, the time and rate of change of the mass? Then I would just use the rate of change and the time to find m(t) and I would solve for a? This is actually for AP Calculus, but I'm pretty sure this concept is a bit advanced for the highschool level (My physics teacher couldn't even help me, which is kind of sad). Please, any help will really be appreciated.