PHYSICS 11 TODAY: • Vectors and Displacement One dimensional motion is the simplest form of motion Example: A train can go only in one dimension forward – backward along the tracks Think about the train….. What about the motion around the train??? Earth is spinning on its axis , so the train must be spinning with Earth Think about the train….. What about the motion around the train??? At the same time, Earth is spinning, around the sun, and so is the train Think about the train….. What about the motion around the train??? At the same time, the sun and the rest of solar system is moving through our galaxy We choose a reference point at a specific time and place against which we will measure changes in position of the train To think about the train’s motion, WE MUST MAKE THINGS SIMPLER! We choose a reference point at a specific time and place against which we will measure changes in position of the train It is called… A system for specifying the precise location of an object in space and time STATION 1 For example: a departing station along the train’s route might be a great frame of reference As an object moves from one position to another, the length of the straight line drawn from its initial to the final position is called: - Each arrows shows the magnitude (size) and direction of a series of a dog’s trips - The arrows are called VECTORS - To give the direction of a vector we use two conventions: NUMERICAL COMPASS (CARDINAL) DIRECTION What is the geckos' displacement? What if I changed zero on the meter stick to the gecko’s initial position? What would be its displacement then? Displacement vs Distance WORLD MAP Homework!! - To determine the angle of the resulting displacement, - To determine the angle of the resulting displacement, we use TRIGONOMETRY GRAPHICALLY Pythagorean Theorem and tangent function (hypotenuse)2 = (leg 1) 2 + (leg 2) 2 leg 2 leg 1 opposite leg tangent of angle = adjacent leg opposite adjacent opposite leg tangent of angle = adjacent leg opposite adjacent 2 d = 2 x + 2 y d = 1928 km Δy 𝜽 = tan−1 ( ) Δx 𝜽 = 37.0˚ What is the velocity that the car must maintain in order to stay underneath the plane? opposite leg sine of angle = hypotenuse adjacent leg cosine of angle = hypotenuse You need to find vx vx cos(𝜽) = ( ) vplane vx = cos(𝜽)(vplane) You need to find vx vx = cos(𝟐𝟎˚)(𝟗𝟓 km/h) vx = 𝟗𝟎 km/h You need to find vx Sand trap Tee shot Putting green Worksheets on Vectors Operations