MasteringPhysics: Homework 7-1 Google Chrome https:// mastering physics.com View
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MasteringPhysics: Homework 7-1 Google Chrome https:// mastering physics.com View? offset next&assignmentProblemID; 61245311 PHY 121 Menendez Spring 2016 Session B Homework 7-1 t Gravitational Force of Three Identical Masses t Gravitational Force of Three Identical Masses Part A Three identical very dense masses of 4100 kg each are placed on the x What is the magnitude of the net gravitational force Frav on the mass at the origin due to the other two masses? axis. One mass is at zi -110 cm one is at the origin, and one is at 440 cm. Take the gravitational constant to be G 6.67 10-11 N /kg Express your answer in newtons to three significant figures Fkrav 9.85 10 Submit Hints My Answers Give Up Review Part Incorrect, Try Again, 2 attempts remaining he origin are identical distance from the origin, so there will be a no ero net force on the ma Although the two masses not they are not the same Help Close Resources previous l 3 of 10 l nextExplanation / Answer
Mass m = 4100 kg
Graviattional force on mass at origin due to mass at -110 cm is F = Gmm/r 2
Where G = Gravitational constant = 1.67 x10 -11 Nm 2/kg 2
r = distance between two masses = 110 cm = 1.1 m
Substitute values you get ,F =(6.67x10 -11)(4100)(4100)/1.1 2
= 9.266 x10 -4 N
Graviattional force on mass at origin due to mass at 440 cm is F ' = Gmm/r 2
Where G = Gravitational constant = 1.67 x10 -11 Nm 2/kg 2
r = distance between two masses = 440 cm = 4.4 m
Substitute values you get ,F ' =(6.67x10 -11)(4100)(4100)/4.4 2
= 5.791 x10 -5 N
F and F ' are opposite to each other.
So, Net force on mass at origin F " = F - F '
= 8.69 x10 -4 N