An Electron and a Positron, Both Essentially at Rest, Annihilate $9.11 \times 10 ^ { - 31 } \mathrm {~kg}$

question 23

Multiple Choice

An electron and a positron, both essentially at rest, annihilate each other, emitting two identical photons in the process. What is the wavelength of these photons? The mass of an electron or positron is $9.11 \times 10 ^ { - 31 } \mathrm {~kg}$ . $\left( h = 6.626 \times 10 ^ { - 34 } \mathrm {~J} \cdot \mathrm { s } , c = 3.00 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } \right)$

• A) \(3.46 \mathrm { pm }\)
• B) \(1.21 \times 10 ^ { - 12 } \mathrm { pm }\)
• C) \(3.07 \mathrm { pm }\)
• D) \(2.42 \mathrm { pm }\)
• E) \(1.73 \mathrm { pm }\)

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A company controlled by a subsidiary of another company, creating a tiered structure of corporate ownership and governance.

Subsidiary Company

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A corporation that owns controlling interest in one or more other companies, referred to as subsidiaries.

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Refers to the Total Non-Controlling Interest in a company, representing the equity in a subsidiary not attributable directly or indirectly to the parent company.