An equilateral triangle 97.0 m on a side has a m 1 = 45.00 kg mass at one corner
ID: 2263763 • Letter: A
Question
An equilateral triangle 97.0 m on a side has a m1 = 45.00 kg mass at one corner, a m2 = 60.00 kg mass at another corner, and a m3 = 125.00 kg mass at the third corner. Find the magnitude and direction of the net force acting on the 45.00 kg mass.
N
Explanation / Answer
F21 = Gm1m2/r^2 = 6.67*10^-11*45*60/97^2 = 1.91*10^-11 N
F31 = Gm1m3/r^2 = 6.67*10^-11*45*125/97^2 = 3.98*10^-11 N
angle between the forces = 60 degrees
Let m3 and m2 lie on postive x-axis
F21 = 120 degrees, F31 = 60degrees with x-axis
F21 = -1.91cos60i + 1.91sin60j *10^-11
F31 = 3.98cos60i + 3.98sin60j *10^-11
net = 2.07i + 5.89j *10^-11
Magnitude = 10^-11*sqrt(2.07^2 + 5.89^2) = 6.243*10^-11 N
Angle = tan^-1( 5.89/2.07) = 70.633 degrees