A6.00 kg crate is suspended from the end of a short vertical rope of negligible mass. an upward force f(t) is applied to the end of the rope, and the height of the crate above its initial position is given by y(t)=(2.80m/s)t +(0.61 m/s3 )t3
what is the magnitude of the force f when 4.40 s ?

In 1995 a research group led by eric cornell and carl wiemann at the university of colorado successfully cooled rubidium atoms to the 20-200 nk temperature range. assuming (incorrectly) that the rubidium atoms behave liké particles of a classical ideal gas, calculate the rms speed of a rubidium atom at a temperature of 112.0 nk. in the experiments one particular isotope of rubidium was used, rubidium-87. the molar mass of this isotope is 86.91 q/mol. tries 0/20 submit answer

Who was the first scientist to measure speed as distance over time?

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