so i have tried this problem fifty million times and i can't get the right answer. hopefully someone can help. when a 75 g mass is suspended from a vertical spring, the spring is stretched from a length of 4.0 cm to a length of 7.0 cm. If the mass is then pulled downward an additional 10 cm, what is the total work done against the spring force in joules? i converted grams to kilograms and cm to m and used the equation f=kx and then plugged those numbers into w=1/2kx^2. i can't get the correct answer of 0.21 J. please help(adsbygoogle = window.adsbygoogle || []).push({});

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# Homework Help: Work against spring force

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