An Electron-Positron Pair Traveling Towards Each Other with a Speed $\rarr$

question 52

Multiple Choice

An electron-positron pair traveling towards each other with a speed of 0.95 c with respect to their center of mass,collide and annihilate according to e^- + e⁺ $\rarr$ $\gamma$ + $\gamma$ .Assuming the observer is at rest with respect to the center of mass of the electron-positron pair,what is the wavelength of the photons?

• A)340 fm
• B)380 fm
• C)760 fm
• D)1200 fm
• E)2400 fm

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Definitions:

Echo

A command in various operating systems that displays messages or turns command echoing on or off in programming environments.

Commands

Instructions given by a user or a program to an operating system or software to perform a specific task.

Environment Variable

A variable that describes the environment in which a program runs. It contains a name and a value, where the value is the path to the program identified by the variable name.

Program

A set of instructions that a computer uses to perform a specific task or operation.