Grindstone#

A uniform cylindrical grindstone has a mass of $params.M\mathrm{k}\mathrm{g}$ and a radius of $params.R\mathrm{c}\mathrm{m}$.

Part 1#

What is the rotational kinetic energy $K\mathrm{\_}\text{rot}$ of the grindstone when it is rotating at $params.RPM\mathrm{r}\mathrm{e}\mathrm{v}/\mathrm{m}\mathrm{i}\mathrm{n}$? You may assume that the grindstone is a solid cylinder rotating about its cylinder axis.

Answer Section#

Please enter a numeric value in $\mathrm{J}$.

Part 2#

After the grindstone’s motor is turned off, a knife blade is pressed against the outer edge of the grindstone with a perpendicular force of $params.F\mathrm{N}$. The coefficient of kinetic friction between the grindstone and the blade is $params.mu$. Use the work energy theorem to determine how many turns $N$ the grindstone makes before it stops.

Answer Section#

Please enter a numeric value.

Attribution#

Problem is from the OpenStax University Physics Volume 1 textbook, licensed under the CC-BY 4.0 license.