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## Homework Statement

Two blocks connected with a massless rope ,are being dragged by a horizontal force.suppose F= 68N, Mass1= 12 ,Mass2=18kg and coeffecient of fraction between each block and surface is 0.10.

12kg ------T--------18kg-----68N--->

Find tension and magnitude of the aceleration of the system

## Homework Equations

f=mg, Fnet= Fa-ff, ff =mu *m*g

## The Attempt at a Solution

Now I have tried to sovle it please see if this is correct or I need to change it----> 1st sloving for acceleration of the system Fnet=Ma

Fnet= Fa+Ff

Ff= (0.10)(9.8)(30)

force of friction= 29.4

so Fnet = 68N +(-29.4)

Fnet= 38.6N

acceleration= Fnet/mass

acceleration = 38.6/30= 1.28 m/s^2

This is probably the answer of the second question.

Now sloving for Tension

F=M_1a ( for 1st mass 12kg)

F= 12*1.28m/s^2

Force on 12kgmass= 15.36N

Force of friction 12kgmass= (12)(9.8)(0.10)= 11.76N

Net force on 12 kg mass= 15.36N+(-11.76)= 3.6N

F=M_2a (for 2nd mass18kg)

F= 18*1.28m/1.28m/s^2

Force on 18kg mass= 23.04

force of friction on 18kg mass=(18)(0.10)(9.8)=17.64

net force on 18 kg mass= 23.04N+(-17.64)= 5.4N

Now the net force on 12 kg mass is 3.6N and net force on 18 kg mass is 5.4N.

am I correct so far if yes , is the tension of the rope one of these values or the sum of these values , if one of these which one and why?