1 DIMENSIONAL VERTICAL MOTION Free Fall an object

1 -DIMENSIONAL VERTICAL MOTION Free Fall - an object dropped from the surface of a planet in the absence of air resistance undergoes “free fall” Acceleration due to the force of gravity, on earth, is known as, “g”. g = -9. 8 m/s/s All objects, on earth, accelerate at the constant rate of -9. 8 m/s/s, in the absence of air resistance.

Air resistance - the force exerted by the air on a falling object

Terminal Velocity - the largest velocity that is reached by a falling object when air resistance balances the pull of gravity the object stops accelerating and speed remains constant = TERMINAL SPEED.

TERMINAL VELOCITY

TERMINAL VELOCITY

UNIFORM ACCELERATION Average Velocity Vav = Dd/Dt Acceleration a = Dv/Dt OBJECTS WITH INITIAL VELOCITY OBJECTS FROM REST Vf = Vi + a. Dt Dx = Vi Dt + ½(a. Dt 2) Vf = sqrt(Vi 2 + 2 a. Dx) Dx = ½(Vi +Vf )Dt Vf = a. Dt Dx = ½(a. Dt 2) Vf = sqrt(2 a. Dx) Dx = ½(Vf )Dt FREE FALL g = 9. 8 m/s/s OBJECTS WITH INITIAL VELOCITY OBJECTS FROM REST Vf = Vi - g. Dt Dy = Vi Dt - ½(g. Dt 2) Vf = sqrt(Vi 2 -2 g. Dy) Dy = ½(Vi +Vf )Dt Vf = -g. Dt Dy = ½(-g. Dt 2) Vf = sqrt(2(-g)Dy) Dy = ½(Vf )Dt

SOURCES http: //www. physicsclassroom. com/mmedia/newtlaw s/sd. cfm http: //www. youtube. com/watch? v=k. NED 5 Rzqx. Oo http: //www. hq. nasa. gov/alsj/a 15/video 15. html#closeo ut 3 http: //www. hq. nasa. gov/alsj/frame. html