Learning Materials
Features
Discover
Chapter 31: Q21PE (page 1149)
Electron capture by 7Be
The 尾- Decay equation of 7Be is \(_4^7B{e_3} + {e^ - } \to _3^7L{i_4} + {\nu _e}\).
.
Over 30 million students worldwide already upgrade their learning with 91影视!
All the tools & learning materials you need for study success - in one app.
Get started for free
A tree falls in a forest. How many years must pass before the 14C activity in 1.00 g of the tree鈥檚 carbon drops to 1.00 decay per hour?
What is the ratio of the velocity of a \(5.00\,{\rm{MeV }}\beta \)ray to that of an\({\rm{\alpha }}\) particle with the same kinetic energy? This should confirm that \({\rm{\beta }}\) s travel much faster than \({\rm{\alpha }}\) s even when relativity is taken into consideration. (See also Exercise \({\rm{31}}{\rm{.11}}\).)
(a) Write the complete \({{\rm{\beta }}^{\rm{ - }}}\) decay equation for the neutron.
(b) Find the energy released in the decay.
: 尾decay producing137Ba. The parent nuclide is a major waste product of reactors and has chemistry similar to potassium and sodium, resulting in its concentration in your cells if ingested.
When an electron and positron annihilate, both their masses are destroyed, creating two equal energy photons to preserve momentum.
(a) Confirm that the annihilation equation \({e^ + } + {e^ - } \to \gamma + \gamma \) conserves charge, electron family number, and total number of nucleons. To do this, identify the values of each before and after the annihilation.
(b) Find the energy of each纬 ray, assuming the electron and positron are initially nearly at rest.
(c) Explain why the two纬 rays travel in exactly opposite directions if the centre of mass of the electron-positron system is initially at rest.
What do you think about this solution?
We value your feedback to improve our textbook solutions.
Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine