A Mathematics Review Unit 1 Presentation 2
Why Review? Mathematics are a very important part of Physics Graphing, Trigonometry, and Algebraic concepts are used often Solving equations and breaking down vectors are two important skills
Graphing Review Graphing in Physics done on a Cartesian Coordinate System Also known as an x-y plane Can also graph in Polar Coordinates Also known as an r, plane Very Useful in Vector Analysis
Rectangular vs. Polar Coordinates Rectangular Coordinate System X-Y Axes Present (dark black lines) X Variable Y Variable Polar Coordinate System NO X-Y Axes R Variable (red lines) Variable (blue/black lines)
Trigonometry Review Remember SOHCAHTOA? Opposite Side Adjacent Side Hypotenuse Side Pythagorean Theorem for Right Triangles:
Using Polar Coordinates To convert from Rectangular to Polar Coordinates (or vice versa), use the following:
Polar Coordinates Example Convert (-3.50 m, m) from Cartesian coordinates to Polar coordinates. But, consider a displacement in the negative x and y directions. That is in Quadrant III, so, since polar coordinates start with the Positive x axis, we must add 180° to our answer, giving us a final answer of 216°
Another Polar Coordinates Example Convert 75 degrees into x and y coordinates. First, consider that this displacement is in Quadrant I, so our answers for x and y should both be positive.
Trigonometry Review Calculate the height of a building if you can see the top of the building at an angle of 39.0° and 46.0 m away from its base. First, draw a picture. 39.0° Building Height 46.0 m Since we know the adjacent side and want to find the opposite side, we should use the tangent ratio.
Another Trigonometry Example An airplane travels 4.50 x 10 2 km due east and then travels an unknown distance due north. Finally, it returns to its starting point by traveling a distance of 525 km. How far did the airplane travel in the northerly direction? First, draw a picture. 450 km 525 km x km This problem would best be solved using the Pythagorean Theorem. N