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Elliott Chick Current University of Exeter MPhys Undergraduate Slide 2 What is it? The Coriolis effect is the apparent deflection of an object in a rotating reference frame. Gaspard-Gustave Coriolis was first to consider this supplementary force. When Newton's laws of motion are applied in a rotation frame of reference, other forces appear. These forces are Fictitious forces and are used as correction factors for the simple application of Newtons laws in a rotating system. Slide 3 Newton's Laws in a rotating reference frame. Slide 4 Slide 5 The Coriolis force Slide 6 An example http://www.europemapofeurope.net/europe- map-of-europe-large-2008-muck-hole.jpg One of the Coriolis effects most common appearance is in ballistics. Target: Ciudad Real Madrid 40.479167 N, 3.611667 W (http://toolserver.org/~geohack/geohack.php?pagename=Ciudad_Real_Madrid&params=40_28_45_N_03_36_42_W_type:landmark)http://toolserver.org/~geohack/geohack.php?pagename=Ciudad_Real_Madrid&params=40_28_45_N_03_36_42_W_type:landmark Distance from Physics Building: 1141 km (http://www.nhc.noaa.gov/gccalc.shtml)http://www.nhc.noaa.gov/gccalc.shtml Tomahawk missile Average speed = 244.4 m/s (sub sonic) Effective range = 2500 km (http://en.wikipedia.org/wiki/Tomahawk_(missile))http://en.wikipedia.org/wiki/Tomahawk_(missile)) of earth = 7.27 x 10 -5 rads/s (http://hypertextbook.com/facts/2002/JasonAtkins.shtml)http://hypertextbook.com/facts/2002/JasonAtkins.shtml Slide 7 An example Slide 8 Slide 9 The Experiment The aim of this experiment was to demonstrate the Coriolis acceleration in a rotating reference frame, and showing that the Coriolis acceleration is proportional to the angular velocity of the rotating reference frame. Apparatus used: (From experiment ME06) Glass turntable (Connected to DC power supply) Covered with paper Metal ramp Ball bearing Slide 10 Experimental setup Slide 11 Experimental method Find the velocity of the ball bearing Time taken to travel between 2 points Measure the angular frequency of the turntable Measure amount of rotations and time taken, use rotations/time to work out revolutions per second Multiply by 2 to find the angular frequency of the turntable Slide 12 Experimental method continued Coat the ball bearing in a layer of ink Place on ramp, with quick release in place Start up the turntable Release the ball The ball will leave behind a trail of dots, allowing easy observation of the path of the ball Slide 13 Analysis Slide 14 Results 1 Slide 15 Results 2 Slide 16 Results 3 Slide 17 Results 4 Slide 18 Conclusions The Coriolis effect can be easily proven using this experimental method From my results I can see that the Coriolis acceleration is proportional to the angular velocity of the rotating reference frame. The velocity was kept constant, thus the only factor effecting the Coriolis acceleration was showing its proportionality.