Find the acceleration in terms of velocity and displacement

AI Thread Summary
The discussion centers on calculating the acceleration of a raindrop falling from clouds, with an increase in mass of 3kg/m as it descends. Participants question the assumption of neglecting drag or air resistance, suggesting that under those conditions, the acceleration should equal gravitational acceleration (g). Concerns are raised about the practicality of the mass increase, noting that gaining 300kg over a 100m fall seems unrealistic for a raindrop. The conversation also touches on the potential for this scenario to be a conceptual test of understanding rather than a practical problem. Overall, the feasibility of the mass increase and its implications for acceleration are the main points of contention.
semc
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Assume a raindrop falls from the clouds and the mass increases as it falls and the increase in mass is 3kg/m. Neglecting any frictional force, find the acceleration in terms of velocity and displacement. Initially when t=0 assume mass is negligible.

I just want to ask if we were to neglect drag or air resist, shouldn't the acceleration be g?
 
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It increases in mass by colliding with water (in some form) that isn't moving. That will slow it down. Is the increase 3kg/m?:confused: That doesn't make sense at all. You'd think it would depend on the size of the raindrop, and that the effect would be 10^4 to10^5 times smaller.
 


semc said:
Assume a raindrop falls from the clouds and the mass increases as it falls and the increase in mass is 3kg/m. Neglecting any frictional force, find the acceleration in terms of velocity and displacement. Initially when t=0 assume mass is negligible.

I just want to ask if we were to neglect drag or air resist, shouldn't the acceleration be g?

Yes, I would think so. Could this be a trick question to test your understanding? if so, I think you understand it :)

If we really wanted to go overboard we could calculate the value of g for different altitudes, but it should be relatively negligible.

Just a quick reality check, is the increase in mass of 3kg/m reasonable? If it fell 100m, it would gain 300kg, that's a pretty heavy raindrop.
 
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