My physics teacher gave me the following two problems as homework and I am completely lost on them.(adsbygoogle = window.adsbygoogle || []).push({});

1) If you cut a spring in half, the k value doubles. An object is attached to the lower end of a 100-coil spring hanging from a ceiling. The spring stretches by 0.16 m. The spring is then cut in half. By how much does each spring stretch?

I don't think he gave me enough information, so I don't know what to do. Any suggestions?

2) A small ball is attached to one end of a spring that has an unstrained length of 0.0200 m. The spring is held at one end and whirled in a horizontal circle at 3m/s. The spring stretches by 0.10m. How much would the spring stretch if the ball was attached to a vertical spring on the ceiling?

I know the spring on the ceiling will stretch less than the spring that is swung in the circle. And the two springs have the same unstrained length. Since I am given velocity, do I use this formula to find the k value?:

1/2kx^2 + mgh(initial height) + 1/2mv^2(initial veloicty) + Work increase = mgh(final height) + 1/2mv^2(final velocity) + Work decrease + 1/2kx^2

Any help will be greatly appreciated!

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# Homework Help: Help with 2 Physics questions

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