Problem to turn in on Thursday

Consider a Ferris wheel, radius 8-m. A 50-kg rider makes 2 rotations per minute. This rider (conveniently) is sitting on a scale.

What will the scale read at the top of the wheel?

What will the scale read at the bottom of the wheel?

How many rotations per minute must the wheel make so the the rider would feel weightless at the top ot the wheel?

Circular motion problems

1. Spinning bucket of water problem. Imagine a bucket of water (mass m) spun in a vertical circle with constant speed (v), if that were possible. What is the minimum speed such the water does NOT fall out of the bucket?

2. Consider a 'loop the loop' (radius r) Roller Coaster. What is the minimum speed for you to travel in a car so that you don't fall out of the roller coaster? Is this the same problem as above?

3. Now consider a roller coaster again - this time, imagine that you are going to the bottom of a curve (with constant radius, r). How does your 'apparent weight' (as measured by a scale that you are conveniently sitting on) vary with the speed of the roller coaster?

4. Consider a car rounding a curve (radius r) with coefficient of friction (u) between wheels and road. What is the relationship between v and u?

HW update

I don't have my text handy and can't post additional problems. However, I'll do so tomorrow - if you can solve them, please do so. If not, I'll understand. At the very least, make sure you're caught up with the older stuff.

hw

Chapter 6:

29

23

55

43

47

homework

Read chapter 6, particularly the sections on drag and circular motion.

There is no derivation for the drag relationship. Feel free to google it, though we will develop it in class.