Math problem

Question

The force in newtons (N) on an object due to the gravity of Earth is directly proportional to the mass of the object and inversely proportional to the square of the distance between the object and the center of the Earth. If a 70 kilogram (kg) object that is 6,380,000 meters away from the center of the Earth feels a force of 685 N due to gravity, then what is the force on a 100 kg object that is 6,390,000 meters away from the center? Round answer to the nearest whole number.

Answer 1

F = GMm/d². according to Sir Isaac; masses are m and M; d is distance between the two masses.

 

Treat M as the mass of the Earth, and incorporate GM as a single constant, which we will rename k.

 

Then the formula is F = km/d²; substitute m=70, d=6,380,000 and F=685.  Then solve for k.

 

Next, using the new k value and m=100 and d = 6,390,000 and you will compute the F that has been requested.