Lab 2: Linear Motion Name Kayleigh Purpose: To experimentally find the velocities of a car as it rolls down a ramp and to use these velocities to calculate the acceleration due to gravity, g. Materials Used: Ramp/track, car, ruler, Vernier LabQuest Mini, Vernier photogates, clamps, protractor. Concept Introduction: The motion of an object is described in terms of four variables: position, velocity, acceleration, and time. The distance (d) an object travels is the difference between its final position and its initial position. If the initial position is defined as zero then the distance is just the final position. The average velocity is defined by the formula: Ax Vavg At t The average acceleration is defined similarly by the formula: davg Av At Note that acceleration changes the velocity of an object which in turn changes its position. Preliminary Questions 1. What is the formula for the slope of a line? ( 42 - 41 ) (X2 -X1 ) 2. What is the equation of a line? y = mx+b Procedure 1. Finding the Acceleration of a Car Down a Ramp. Set up a ramp as indicated by your instructor. Using a protractor, measure the angle 0 the ramp makes with the horizontal. You may wish to measure distances to calculate the angle as well. Slope of Ramp 0 = 2. Open Logger Pro and connect both photogates to the interface. The photogate nearest the top of the ramp should be plugged into the "Digital 1" input and the photogate nearest the bottom of the ramp should be plugged into "Digital 2" input. Set the track stop at the 2 cm mark and the car 20 cm above this point. With the "picket fence" in the car, the photogate nearest the bottom of the ramp should be just above the black rectangle at the top of the picket fence. The photogate at the top of the ramp should be just in front of the rectangle. The photogate near the bottom of the ramp should be set for "Gate Timing". You'll also have to Set Distance or Length" to 0.0254 m. The photogate near the top of the ramp should be set for "Motion Timing". Pres he spacebar and release the car. Press the spacebar again after the car reflects off the track stop