Peoples Physics Concepts

9.5. Yo-Yo Type Problems http://www.ck12.org

T=

1

2 mr

(^2) α
r
substituting forI
T=

1

2

mr^2

a

r

1

r

substituting forαin terms ofa

T=

1

2

ma simplifying the equation.

We can now plug this back into our original Newton’s second law equation from the first step.

mg−T=ma start with the equation from we derived in the first step

mg−

1

2

ma=ma substitute for T

a=

2

3

g simplifying and solving for a

Watch this Explanation

MEDIA

Click image to the left for use the URL below.

URL: http://www.ck12.org/flx/render/embeddedobject/408

MEDIA

Click image to the left for use the URL below.

URL: http://www.ck12.org/flx/render/embeddedobject/1874

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