- #1
PhySci83
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Homework Statement
A 2.0-kg mass (m1) and a 3.0-kg mass (m2) are on a horizontal, frictionless surface, connected by a massless spring with spring constant k = 140 N/m. A 15-N force (F) is app0lied to the larger mass, m2, as shown in the figure:
|__m1__|-/-/-/-/-|____m2____| ----------> F
Show that the magnitude of the spring force (spring tension) is given by:
Fs= F(1/(1+(m2/m1))) <---Sorry, do not know how to make that look more asthetically pleasing.
Homework Equations
F = ma
Fs = -k(xf-xi)
The Attempt at a Solution
Since I am looking for the Fs, I attempted to find the net force of the system with the direction of the force being the positive x direction and the N force of the masses being the positive y.
So for the F going to the right, I said F = (m1+m2)*a; a = F/(m1+m2).
For the F of the spring, I said Fs = -k(xf-xi) and rearranged the equation so that delta_x = magnitude_F/K; delta_x=(ma)/K; then I plug in the value for a that I solved prior.
The problem is, I keep going around in circles with this thing. I am pretty far removed from basic HS math, but if the F wasn't pulled out of the equation, would it be:
Fs = F/(F + [(F*m2/F*m1)])?
Any help that would point me in the right direction would be greatfully appreciated. It seems like I have to solve for the various variables and plug them into the original equation:
Fs = -k(xf-xi)
but getting rid of K and delta_x are troubling me.