Your roommate is working on his bicycle and has the bike upside down. He spins the 60-cm-diameter wheel, and you notice that a pebble stuck in the tread goes by four times every second. What is the centripetal force? i know the speed is 7.5 m/s and the equation is a=v^2/r but it keeps on giving me the incorrect answer of 1.875. Help!!(adsbygoogle = window.adsbygoogle || []).push({});

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# Could someone help me solve this problem?

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