Transcript Up, Up and Away
Up, Up and Away January 25, 2006 Calendar Today – Some problems on vectors – Introduction to some 2D issues Friday, Monday – 2D Kinematics Wednesday – Exam #1 – Through 2D Stuff finished on Monday Friday – Going around in circles Find the horizontal and vertical components of the d = 140 m displacement of a superhero who flies from the top of a tall building following the path shown in the Figure where = 30.0°. Superperson The helicopter view in Figure P3.35 shows two people pulling on a stubborn mule. Let the magnitude of F2 = 64.0 N and the angle at which F1 pulls be = 65.0°. (a) Find the single force that is equivalent to the two forces shown. The forces are measured in units of newtons (symbolized N). (b) (b) Find the force that a third person would have to exert on the mule to make the resultant force equal to zero. (c) Use I,j notation 2 Dimensional Motion We will consider motion the the x-y plane. Positions now have (x,y) coordinates so we need to use vectors. That’s why we did that pointy stuff on Monday There are two types of problems we need to consider Throw or drop an object at an angle to the horizontal Make something go around in a circle Positions are VECTOR quantities ri r r f ri r f r Velocities Which way is the acceleration? In 2D motion, lots of things happen at once! Velocity Position An Example … What is its velocity here? It’s acceleration? How long did it take to get here? here? height (h) RANGE (R) Let’s Just Do it! The Monkey Problem – Hit or Miss? Angle??