COMEDK · Physics · 17. Electrostatics
Distance between the two point charges is increased by \(20 \%\). Force of interaction between the charges
- A increases by \(10 \%\)
- B decreases by \(20 \%\)
- C decreases by \(17 \%\)
- D decreases by \(31 \%\)
Answer & Solution
Correct Answer
(D) decreases by \(31 \%\)
Step-by-step Solution
Detailed explanation
Force between two point charges is given by \(F=\frac{k q_{1} q_{2}}{r^{2}}\) When \(r^{\prime}=r+20 \%\) of \(r=1.2 r\), then \(F^{\prime}=\frac{k q_{1} q_{2}}{(1.2 r)^{2}}=\frac{k q_{1} q_{2}}{1.44 r^{2}}=\frac{F}{1.44}\) Percentage decrease in force…
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