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Angular rotation

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The drill used by the most dentists today is powered by a small air-turbine that can operate at angular speeds of 350000 rpm. These drills, along with ultrasonic dental drills, are the fastest turbines in the world-far exceeding the angular speeds of jet engines. Suppose a drill starts at rest and comes up to operating speed in 2.0 s. Part A: Find the angular acceleration produced by the drill, assuming it to be constant.   Express your answer using two significant figures Step 1:  ω = 350000 rpm (revolution per minute), but in SI unit is rad/s so we have to convert to rad/s.  1 rev = 2 π rad 1 min = 60 s So we get  ω =  (350000 rev)*(  2 π rad/rev)*(1/60 s/m) =36651.9 rad/s Step 2: the drill starts at a rest so we get initial angular speed:  ω0 = 0 rad/s Time to exceed the angular speeds of jet engines: Δt = 2 s what is angular acceleration: α = ? Step 3: ω =  ω0 +  α*t <=>  ω =   α*t =>  α =...

My favorite resources.

Hi everyone, Now I want to share some great resources may help while solving problem 1. Yahoo. Yahoo where everyone has asked many questions. So you can go there and search the answer may help you. Sometimes, I try to check it out if there are some interesting problem to learn. And of course, here is the link:  https://answers.yahoo.com/dir/index?sid=396545211 2. Lecture Online: This is a good website which has a main formulas. They also have most of specific problems which can happens. Yeah, I love it because they solve the problems very details. Here we go:  http://www.ilectureonline.com/lectures/subject/PHYSICS/1/15 3. Google: When you search a specific problem, but you can find the answer, or not good answer. You should search the keywords, and find the situations similar to the problem you want to solve. This way help you more understand about it. Besides that, image search and video search functions from google are very helpful. Link? Hm, lazy boy,  https://www....

Introduction

Hi everyone, Thanks for visiting my blog. My name is An Lam. I am a student from Lone Star Cy-fair college (" http://www.lonestar.edu/cyfair.htm ") I really love physics. I know you guys love it too. Right? I am currently taking physics 1401. While my classmates and I doing homework, there are some problems that people from others group, or class doesn't know how to solve it. My blog will concentrate on what currently studying in Lone Star right now. I hope it will help you and me understand 100% what we are studying. Enjoy, Thanks!