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NEET PHYSICSGRAVITATIONEasy

Question

In a gravitational field, the gravitational potential is given by V=KxV=-\frac{K}{x} J/kg. The gravitational field intensity at the point (2,0,3)(2,0,3) m is:

A

+K2+\frac{K}{2}

B

K2-\frac{K}{2}

C

K4-\frac{K}{4}

D

+K4+\frac{K}{4}

Step-by-Step Solution

  1. Relationship between Field and Potential: The gravitational field intensity (II or EE) is the negative gradient of the gravitational potential (VV). In one dimension (since VV depends only on xx), the relationship is given by: I=dVdxI = -\frac{dV}{dx} (Reference: Concept of conservative forces, F=dV/dxF = -dV/dx, applied to unit mass ).
  2. Differentiation: Given V=Kx1V = -Kx^{-1}. Differentiating with respect to xx: dVdx=ddx(Kx1)=K(1)x2=Kx2\frac{dV}{dx} = \frac{d}{dx}(-Kx^{-1}) = -K(-1)x^{-2} = \frac{K}{x^2}
  3. Calculation: Substitute the derivative back into the field equation: I=(Kx2)=Kx2I = -\left( \frac{K}{x^2} \right) = -\frac{K}{x^2}
  4. Substitution: At the point (2,0,3)(2, 0, 3), the value of xx is 22. Substitute x=2x=2: I=K22=K4I = -\frac{K}{2^2} = -\frac{K}{4} The gravitational field intensity is K4-\frac{K}{4} N/kg (or J/kg/m).

Exam Context & Concepts Covered

This question aligns with the NEET PHYSICS syllabus, specifically targeting concepts from GRAVITATION. Mastering this topic is crucial for scoring well in the upcoming medical entrance examinations. Solving conceptually related problems will help you understand the nuances of these concepts and improve your problem-solving speed.

PHYSICSGRAVITATIONgravitationalgravitationalpotentialvfrackxgravitational

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