A 1 kg object is located at a distance of 1.0 x 103 m from the center of a larger object whose mass is 2.0 x 1020 kg.
a. What is the size of the force acting on the smaller object?

The force = 1.334 x 10⁴ N

Gravity is a force that arises because of the attraction between objects with mass.  

The magnitude of this attraction is proportional to the mass of the object.  

The greater the mass of the object, the greater the gravitational force  

Relationships can both be stated in  

Newton's Gravity Law:  

with F = gravitational force,  N

G = gravitational constant,  6.67 x 10⁻¹¹ Nm²/kg²

m1, m2 = mass of object,  kg

r = distance between two objects.  m

m₁= 1 kg

m₂=2 x 10²⁰ kg

r = 1 x 10³ m

The force acting on the smaller object=The force acting on the larger object(Newton's Third Law)

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.