In the figure above, two small objects (magnets for instance) of the same mass exert forces on each other of a magnitude F. When object A is subjected to an external force of 3.6x10^-2 N, A accelerates at 1.6 m/s/s and B accelerates at 2.1 m/s/s as shown. Find F. Neglect other forces, assume accelerations are parallel.
ƩF = ƩmƩa
The Attempt at a Solution
I'm not sure if the solution i got is entirely correct but this is it
ƩF(A) = 3.6x10^-12
ƩF(B) = (3.6x10^-2) + F
I got this because B is accelerating faster which means the force on B must be greater if the masses are equal.
Using this, I found the mass of A, by F = ma
3.6x10^-2 = m(1.6)
m = .0225 kg, so A and B are .0225 kg
To find F, I substitute the mass into F = ma for F(b)
(3.6x10^-2)+ F = .0225*2.1
F = 1.13x10^-2 N
Is that correct?
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