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## Homework Statement

Find the time it takes for block A to slide 0.5m on block B.

Mass A=10 kg

Mass B=35 kg

I included a screen shot from my online homework.

## Homework Equations

F

_{R}=F

_{N}μ

_{k}

## The Attempt at a Solution

For Block A:

m

_{A}a=T-F

_{RA}-W

_{A}sin(30)

T=10a+68.67

For Block B:

F

_{RC}=(m

_{A}g+m

_{B}g)μ

_{BC}

F

_{RA}=m

_{A}gμ

_{AB}

m

_{B}a=T+F

_{RC}-F

_{RA}-W

_{A}sin(30)-W

_{B}sin(30)

After substituting in all my values:

35a=T-196.2

T=35a+196.2

Setting my Tensions equal to each other:

10a+68.67=35a+196.2

magnitude of a=5.1012

Finding time:

s-s

_{0}=0.5at

^{2}+v

_{0}t

s

_{0}=0

v

_{0}t=0

0.5=.5(5.1012)t

^{2}

t=0.443s

Which is wrong... I can't figure out what exactly I'm doing wrong.