10. Extra: An elephant is located on Earth's surface at a latitude d. (a) What is the angular speed and (b) the linear speed of the elephant on Earth's surface at latitude 40° N. (c) At what latitude would its linear speed be 10 m/s?

4. A circular saw blade rotating at 3600 rpm is braked to a stop in 6 sec. What is the angular acceleration? How many revolutions did the blade make before coming to stop?

It has been suggested that rotating cylinders about 18.5 mi long and 4.60 mi in diameter be placed in space and used as colonies. What angular speed must such a cylinder have so that the centripetal acceleration at its surface equals the free-fall acceleration on Earth? rad/s

1) The picture to the right shows an ad for an old piece of playground equipment called a Giant Stride. We had one at my elementary school, it was pretty fun. I don't think they let kids play on this sort of thing these days. Chains with handles on one end are connected to the top of a pole where they are free to rotate. When the children run in a circle they can get going fast enough to fly off the ground as they move in a horizontal circle. What is the linear speed of a child when the chain she is holding makes an angle of 35° with the vertical? Assume the chain is 4 m long. Price of Head Complete with 6 Ladders, Any Type No Pipe. $26.75 No. 16. No. 15. Supporting Post, Painted $15.25

2. We can use a simple model which uses our understanding of uniform circular motion to estimate the largest possible rotational speed of a planet around its own axis. For a planet of mass M and radius R our model assumes that the planet "falls apart" when the loose rocks on the surface at the equator are no longer sitting on the surface because they leave the surface. A loose rock of mass m is shown on the equator in the drawing. M m R С. Now return to the 'slowly' rotating planet (where the loose rocks are not flying off the surface) and consider a loose rock that is not on the equator, but at some higher latitude, 0 (as shown). Do you need forces besides gravity and the normal force to make this situation possible? Justify your answer (you just need to justify whether you need another force but not what that other force might be if it is needed).

1. A wind turbine is rotating at 31 rev/min. How fast (in m/s) is a point on the blade is moving that is (a) 0.5 m from the rotational axis? Answer: m/s (b) 1.0 m from the rotational axis? Answer: m/s (c) What is the magnitude of the centripetal acceleration at 0.5 m? Answer: V m/s? (d) What is the magnitude of the tangential acceleration at 0.5 m? Answer: V m/s2

question 4

7.

1. Lynne jogs daily around a circular track of diameter 25m for a total distance of 942 m in 5.0 min. How many times did Lynne jog around the track? What is Lynne's average angular speed in radians/s?

17. A satellite orbits the Earth near the equator at a distance of 300 km from the Earth's surface. Use your determination of the tangential velocity of the satellite as it orbits the Earth to calculate its orbital period. a. 14 minutes b. 84 minutes 90 minutes None of these are correct C. d.