The Current in an Electron Beam in a Cathode-Ray Tube

question 105

Multiple Choice

The current in an electron beam in a cathode-ray tube is measured to be 280 µA. How many electrons hit the screen in 50 s? (e = 1.6 *10 ^{- 19} C)

• A) 2.2 * 10¹¹ electrons
• B) 8.8 * 10¹⁶ electrons
• C) 8.8* 10¹⁵ electrons
• D) 2.2 * 10¹⁵ electrons

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