Question

two spheres of masses 100kg and 900kg each of radius 10m and 20m respectively. Find gravitational force acting between them.​

Answer 1

Answer:

gravitational force is equal to m1+m2/(r1+r2)2=100+900/100+400=1000/500=2

Answer 2

Answer:

The gravitational force between the spheres is 6.003 x 10⁻⁶ /(10+x+20)² N .

Explanation:

Given that :

• mass of first sphere, m1 = 100 Kg
• mass of second sphere, m2 = 900 Kg
• radius of first sphere, r1 = 10m
• radius of second sphere = 20 m

Solution :

• Let, the two spheres of mass m1 and m2 are r distance apart measured from the centre of spheres.
• The force of attraction between these two spheres is given by

$F = G \frac{m1m2}{ {r}^{2} }$

• where, G is the Universal Gravitational Constant
• G = 6.67 x 10⁻¹¹Nm²Kg⁻²
• Let, us assume that the distance between the outer points of two spheres be x.
• Total distance between two spheres measured from their centre is (10 + x + 20)m
• The gravitational force acting between the spheres is

$F = G \frac{100 \times 900}{ {(10 + x + 20)}^{2} } \\ = 6.67 \times {10}^{ - 11} \times \frac{9 \times {10}^{4} }{ {(10 + x + 20)}^{2} } \\ = \frac{6.003 \times {10}^{ - 6}}{ {(10 + x + 20)}^{2} } N$