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PHY 102 ELECTROSTATICS Objective Question
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Question

According to the document, the work done by the electrostatic field in moving a charge q from point A (radial distance rA) to point B (radial distance rB) in the field of a positive charge Q is given by which of the following expressions?
Options
A <code>(Qq / (4πε₀)) * (1/r<sub>A</sub> - 1/r<sub>B</sub>)</code>
Correct Answer
B <code>(Qq / (4πε₀)) * (1/r<sub>B</sub> - 1/r<sub>A</sub>)</code>
C <code>(4πε₀ / Qq) * (r<sub>B</sub> - r<sub>A</sub>)</code>
D <code>(Qq / (4πε₀)) * (r<sub>B</sub> + r<sub>A</sub>)</code>
Correct Answer

Option A is the correct answer.

Detailed Explanation

The document, on page 15, states that the work done by the field (Equation 3.4) is the integral of (Qq / (4πε₀r²)) dr from rA to rB. This evaluates to Qq / (4πε₀) * (1/rA - 1/rB). The work done by the environment is the negative of this.

Hint

Refer to equation 3.4 on page 15, which explicitly defines the work done by the field.

Question Info

Course: PHY 102
Topic: ELECTROSTATICS
Type: Objective
Difficulty: Not specified
Question 785 of 1819
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