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The nucleus of the polonium isotope 214 Po (mass 214 u) is radioactive and decays by emitting an alpha particle (a helium nucleus with mass 4 u). Laboratory experiments measure the speed of the alpha particle to be 1.97×107 m/s.

Assuming the polonium nucleus was initially at rest, what is the recoil speed of the nucleus that remains after the decay?

User Mory
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2 Answers

3 votes

Answer:

368224.29906

Step-by-step explanation:

User Himanshu Mori
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1 vote

Answer:

368224.29906 m/s

Step-by-step explanation:

M = Mass of Polonium nucleus = 214 u

V = Velocity of nucleus

m = Mass of Helium nucleus = 4 u

v = Velocity of alpha particle =
1.97* 10^7\ m/s

In this system the momentum is conserved


MV+mv=0\\\Rightarrow MV=-mv\\\Rightarrow 214V=-4* 1.97* 10^7\\\Rightarrow V=(-4* 1.97* 10^7)/(214)\\\Rightarrow V=368224.29906\ m/s

The recoil speed of the nucleus that remains after the decay is 368224.29906 m/s

User PriyankaK
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