Chapter 2 Motion in One Diension Sharyland ISD Overview2章一维运动 Sharyland ISD概述.pptVIP

Motion with constant acceleration. Velocity Vs. Time Graphs Review - Displacement with constant uniform Acceleration Displacement depends on acceleration, initial velocity, and time. Displacement with constant uniform acceleration is equal to : ΔX = ? (initial velocity + final velocity)(time interval) Solving for Final Velocity (Vf) Final velocity depends on initial velocity, acceleration, and time. aavg = Δv = vf - vi Δt tf - ti Displacement of an object depends on initial velocity, final velocity, and time. Δx = ? (vi + vf) Δt How can we solve for displacement if we don’t have final velocity? Solving for Vf Displacement By rearranging the equation for acceleration, we can find a value for the final velocity. vf = vi + aΔt To find displacement of an object moving with uniform acceleration we substitute the above expression for vf into our displacement formula. Δx = vi Δt + ? a(Δt)2 Guided Practice Sample Problem 2D on pg. 55 Final Velocity after Any Displacement We can also obtain an expression that relates displacement, velocity, and acceleration without using time interval. vf2 = vi2 + 2aΔx Guided Practice Sample Problem 2E pg. 57 SECTION 3 FALLING OBJECTS Chapter 2 One Dimensional Motion Free Fall Free fall is acceleration due to gravity. Free fall acceleration is constant. Magnitude of free fall is 9.81 m/s2 Direction of free fall is directed downward. negative direction (-) Free fall is denoted with the symbol g. (Sometimes may be ‘a’ for acceleration due to gravity) Free Fall In a vacuum, in the absence of air resistance, all objects fall at the same rate. What goes up must come down. What causes an object that has been thrown up into the air to come back down? Free-Fall Acceleration due to gravity is always directed downward and pulling an object towards Earth’s surface. Rec