6. at the north pole, a pendulum day is 12 hours. at what latitude is a pendulum day 24 hours? 48 hours? 7. often people refer to the "coriolis force", but the class notes also refers to the "coriolis acceleration". explain how we know a coriolis acceleration should have the same units as "coriolis force per mass". 8. what latitude is washington dc (to the nearest degree)? at this latitude, a) what is the coriolis acceleration on some water moving at 5 cm/s? b) at the same latitude, what is the coriolis acceleration on a car travelling at 20 m/s? c) how fast is 20 m/s in miles per hour? d) an object travelling at speed u in a circle of radius r has an acceleration towards the center of the circle ofa -u2/r. what is the acceleration of water flowing at 5 cm/s in a 100 km wide eddy, and of a car driving at 20 m/s around a curve with radius 200 m? e) why do we need to consider the coriolis force when we study ocean currents but not when we drive a car? 9. the figure shows time-average sea surface height in part of the north atlantic, as measured by satellite altimeters. at each of the points a, b, and c in the chart: a) what is direction and magnitude of pressure gradient force? b) what is direction of coriolis force due to the geostrophic velocity? c) what is the direction and magnitude of geostrophic velocity? climatological sea surface height blue negativev pink: positive values tour interval 10 cm