MCQ
Gravitational force between two identical uniform solid gold spheres of radius r reach in contact is proportional to
- ✓$r^4$
- B$r^2$
- C$\frac{1}{{{r^2}}}$
- D$\frac{1}{{{r^3}}}$
✓
Answer
Correct option: A.
$r^4$
a
$\mathrm{F}=\mathrm{Gm}^{2}$
$\mathrm{F}=\mathrm{Gm}^{2}$
$(2 \mathrm{r})^{2}$
$\mathrm{m}=\rho \times \frac{4}{3} \pi \mathrm{r}^{3}$
$\mathrm{F}=\mathrm{G} \rho^{2} \times \frac{16 \pi^{2}}{9} \times \frac{\mathrm{r}^{6}}{4 \mathrm{r}^{2}} \propto \mathrm{r}^{4}$
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