A hot-air balloon is ascending at constant velocity. At the instant a package is released from the balloon, the momentum of the balloon:
A. Increases
B. Decreases
C. is unaffected because the force does not change
D. is unaffected because the decrease in mass is compensated by an increase in velocity
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BR key says that A is correct. The only way I can conceptualize this, based on BR's explanation, is that when the book is tossed it gains some momentum (mass of book X velocity) in the DOWNWARD direction. In order to conserve momentum for the balloon-book system, the upward momentum would have to increase. I'm not sure why it's conceptually more difficult than the linear momentum problems I'm used to.
If anyone has a better explanation I'd love to hear it!
A. Increases
B. Decreases
C. is unaffected because the force does not change
D. is unaffected because the decrease in mass is compensated by an increase in velocity
---
BR key says that A is correct. The only way I can conceptualize this, based on BR's explanation, is that when the book is tossed it gains some momentum (mass of book X velocity) in the DOWNWARD direction. In order to conserve momentum for the balloon-book system, the upward momentum would have to increase. I'm not sure why it's conceptually more difficult than the linear momentum problems I'm used to.
If anyone has a better explanation I'd love to hear it!
