Two identical blocks are tied together with a string and placed along the same radius of a turntable that is spinning about its center. The inner block is 4 cm from the center and the outer block is 5 cm from the center. The coefficient of static friction between the turntable and the blocks is µs = 0.74, and the string is taut.(adsbygoogle = window.adsbygoogle || []).push({});

a) What is the maximum angular frequency such that neither block slides?

I got w= 12.7 which was right

b) Now suppose that the blocks each have a mass m = 21 g. For the value of w you just found, what is the tension in the string?

T= ?N

I am stuck on b) I have 2 eqns:

T+[tex]\mu[/tex]mg=mR_{1}w^2

-T+[tex]\mu[/tex]mg=mR_{2}w^2

So I keep getting 17N each time I try. What am i doing wrong?

T=mR_{1}w^2-[tex]\mu[/tex]mg

=21x.05x12.7^2 - .74x21x9.81

=169.4-152.4= 17N

Help Please!

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# Homework Help: Blocks on a Turntable

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