Question:
Which one of the following pairs of charges separated by the same distance r will experience a maximum force?
Which one of the following pairs of charges separated by the same distance r will experience a maximum force?
Show Hint
For a fixed sum, the product is maximum when the two values are equal ($q_1 = q_2$).
Updated On: Apr 28, 2026
- 0.3 C and 0.7 C
- 0.1 C and 0.9 C
- 0.2 C and 0.8 C
- 0.5 C and 0.5 C
- 0.4 C and 0.6 C
Show Solution
Verified By Collegedunia
The Correct Option is D
Solution and Explanation
Step 1: Concept
Coulomb's Law states $F = k \frac{q_1 q_2}{r^2}$. For constant $r$, force is maximum when $q_1 \times q_2$ is maximum.
Step 2: Analysis
Calculate the product for each pair (where the sum of charges is constant at 1.0 C): (A) $0.3 \times 0.7 = 0.21$ (B) $0.1 \times 0.9 = 0.09$ (C) $0.2 \times 0.8 = 0.16$ (D) $0.5 \times 0.5 = 0.25$ (E) $0.4 \times 0.6 = 0.24$
Step 3: Conclusion
The product is maximum for pair (D). Final Answer: (D)
Coulomb's Law states $F = k \frac{q_1 q_2}{r^2}$. For constant $r$, force is maximum when $q_1 \times q_2$ is maximum.
Step 2: Analysis
Calculate the product for each pair (where the sum of charges is constant at 1.0 C): (A) $0.3 \times 0.7 = 0.21$ (B) $0.1 \times 0.9 = 0.09$ (C) $0.2 \times 0.8 = 0.16$ (D) $0.5 \times 0.5 = 0.25$ (E) $0.4 \times 0.6 = 0.24$
Step 3: Conclusion
The product is maximum for pair (D). Final Answer: (D)
Was this answer helpful?
0
0
Top KEAM Physics Questions
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- Two capillary tubes A and B of diameter $1\, mm$ and $2\, mm$ respectively are dipped vertically in a liquid. If the capillary rise in A is 6 cm, then the capillary rise in B is
- In the circuit given in figure, 1 and 2 are ammeters. Just after key K is pressed to complete the circuit, the reading will be
- A plate has a length $ 5\pm 0.1\text{ }cm $ and breadth $ 2\pm 0.01\text{ }cm $ . Then the area of the plate is:
View More Questions
Top KEAM coulombs law Questions
- Two identical conducting spheres carrying different charges attract each other with a force $ F $ when placed in air medium at a distance $ d $ apart. The spheres are brought into contact and then taken to their original positions. Now the two spheres repel each other with a force whose magnitude is equal to that of the initial attractive force-The ratio between initial charges on the spheres is
- Around a stationary charge of +5µC, another charge -5µC is taken once round a circle of radius 4 cm. The amount of work done in Joule is
- A given charge \( Q \) is divided into two parts which are then kept at a distance \( d \) apart. The electrostatic force between them will be maximum if the two parts are
- The electrostatic force between two point charges at a distance of separation \(d\) is \(F\). If one of the charge is moved away by a distance \(d/2\) then the force between them is
- Force between two charges \( +8\,\mu C \) and \( +2\,\mu C \) is \( 16\,N \). If the charges are brought into contact and then separated by the same distance, the force between them is
View More Questions
Top KEAM Questions
- i.$\quad$ They help in respiration ii.$\quad$ They help in cell wall formation iii.$\quad$ They help in DNA replication iv. $\quad$They increase surface area of plasma membrane Which of the following prokaryotic structures has all the above roles?
- A body oscillates with SHM according to the equation (in SI units), $x = 5 cos \left(2\pi t +\frac{\pi}{4}\right) .$ Its instantaneous displacement at $t = 1$ second is
- The pH of a solution obtained by mixing 60 mL of 0.1 M BaOH solution at 40m of 0.15m HCI solution is
Kepler's second law (law of areas) of planetary motion leads to law of conservation of
- If $\int e^{2x}f' \left(x\right)dx =g \left(x\right)$, then $ \int\left(e^{2x}f\left(x\right) + e^{2x} f' \left(x\right)\right)dx =$
View More Questions