Question

two spheres of same material of density 8000kg/m³ and radius 1m are in contact with each other then the gravitational force btw then is nearly :
a)1.9 ×10‐⁵N
b)2.9 × 10-⁵N
c)19 ×10-⁵ N
d) 1.9 × 10-² N​

Answer 1

Answer:

$F = G \frac{MM }{ {r}^{2} } \\ \\ = G \frac{( \rho V) {}^{2} }{ {r}^{2} } \\ \\ = 6.67 \times {10}^{ - 11} \times \frac{(8000 \times 1) {}^{2} }{ {2}^{2} } \\ \\ = 16 \times 6.67 \times {10}^{ - 5} \\ \\ = 1.06 \times 10 {}^{ - 3} \: newton$

It's right answer I cross checked with calculator .

** We take r distance between centres