NEET
- Exam
- NEET
- Subject
- Physics
- Chapter
- Gravitation
NEET · Physics · Gravitation
The mass density of a spherical body is given by ρ(r) = (k)/(r) for...
The mass density of a spherical body is given by for and for where r is the distance from the centre. The correct graph that describes qualitatively the acceleration, a, of a test particle as a function of r is :




Options
- A
- B
- C
- D
Correct answer
A.
Step-by-step solution
For Inside point
For outside point \left(r > R\right)E = g = \dfrac{GM}{{r}^{2}} = \dfrac{G}{{r}^{2}} \mathop{∫}_{0}^{R} ( 4\pi{r}^{2} d{r}^{′} )( \dfrac{K}{{r}^{′}} ) = \dfrac{4\piKG}{{r}^{2}} {[ \dfrac{{{r}^{′}}^{2}}{2} ]}_{0}^{R}E = g = \dfrac{2\piKG}{{r}^{2}}{R}^{2}E ∝ \dfrac{1}{{r}^{2}}