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Q & A: radioactive recoil

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Most recent answer: 09/09/2014
Q:
1.In a radioactive decay does the radioactive element feel any reaction force (from newton's third law) as particles and energy gets out of it ? or does the center of mass of that radioactive element remains same ? 2.on the basis of newtonian gravity how much time should a non symmetrical change of mass of sun take to reach earth ?
- Raktim Singha Roy (age 31)
Malda, West Bengal, India
A:

1. Yes, there certainly is momentum conservation and thus recoil in radioactive decay.

2. Newtonian gravity includes no propagation delay. In actual gravity (general relativity) it takes about 8 minutes for some change at the Sun to propagate to Earth.

Mike W.


(published on 09/09/2014)

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