What Are the Tensions in Two Blocks With Friction and Acceleration?

AI Thread Summary
The discussion revolves around calculating the tensions in two strings connected to two blocks with given masses and a coefficient of friction. For block m1 (80 kg), the horizontal forces include T1, T2, and friction, leading to the equation T1 - T2 - Ff = m1 * a. The friction force for m1 is calculated as 109.8 N, and T2 is determined to be 137.2 N for block m2 (100 kg). The final tension T1 is calculated to be 407 N, and the suggestion is made to first consider the system as a single block to simplify the calculations. The approach to solving the problem is confirmed as correct.
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Homework Statement


Two blocks of mass m1=80 kg and m2=100 kg and attached by a string, another sting comes off of mass m1 and is pulled horizontally (kinda looks like this) (T1 & T2 are tensions)
m2--T2--m1--T1--> there is a coefficient of friction u=.14 for both blocks, what is the tension in both strings while the system accelerates at 2 m/s^2?


Homework Equations


Fnet=ma
Ff=u(N)

The Attempt at a Solution


Ok so for m1 horizontal forces are T1 to the right, T2 to the left and friction.
T2=(100)(9.8)(.14)=137.2 N Friction for m1=(80)(9.8)(.14)=109.8
So T1-T2-Ff = m1*a therefore T1=(80)(2)+(109.8)+137.2= 407 N
Is this Correct??
Thanks!
 
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First consider the 2 block system as a 1 block system (combine their masses) then you can solve T1. Once you have this you can distribute T2 appropriately.
 
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