A Positron and an Electron, Each with a Rest Mass

question 37

Multiple Choice

A positron and an electron, each with a rest mass of 0.511 MeV/c² and traveling at 50% the speed of light towards one another, annihilate. How much energy, in MeV, is released?

• A) 1.36 MeV
• B) 1.18 MeV
• C) 1.02 MeV
• D) 0.89 MeV
• E) 1.53 MeV

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Definitions:

Silica Tetrahedron

A structural unit of silicon ion surrounded by four oxygen ions, forming the basic building block of silicate minerals.

Silicon

The fourteenth element in the Periodic Table, having the atomic symbol Si.

Silica Tetrahedra

The basic structural unit of silicate minerals, consisting of four oxygen atoms surrounding a single silicon atom.

Silicate Minerals

A group of minerals that contain silicon and oxygen, usually with other metals, forming the largest and most important class of minerals on Earth.