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Two electrons are ejected in opposite directions from radioactive atoms in a sample of radioactive material. Let c denote the speed of light. Each electron has a speed of 0.67 c as measured by an observer in the laboratory. Their relative velocity is given by ______.

#### Options

1.34 c

1.19 c

0.92 c

0.87 c

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#### Solution

Two electrons are ejected in opposite directions from radioactive atoms in a sample of radioactive material. Let c denote the speed of light. Each electron has a speed of 0.67 c as measured by an observer in the laboratory. Their relative velocity is given by **1.34 c**.

**Explanation:**

Vrel = `"V"_2 - "V"_1 = .67 "C" - (- .67 "C")` = 1.34 C

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