PHYSICS 1408 LAMP CHAPTER 2 NOTES VERTICAL ACCELERATION dropping things Acceleration of gravity g 9 8 m s2 Acceleration in the vertical direction Ay Variables Ay g Examples 1 A person drops a ball off the side of a 1000 m tall building What is the velocity of the ball right before impact with the ground Given h 1000 m Solving For Vyf Vyi 0 m s since the ball is dropped it has no initial velocity Ay g g 9 8 m s2 Yi h Yf 0 The kinematics equation needed Vf 2 Vi 2 2ay y Plug and Chug Vf 2 0 m s 2 9 8 m s2 1000 m Vf 2 19600 m2 s2 Vf 140 m s since the ball is moving in the negative direction we interpret the velocity as negative too The ball is moving at a velocity of 140 m s the instant before it hits the ground 2 A ball is thrown directly upward with an initial velocity of 20 m s It reaches a certain height h and the falls down to its initial position What is h Given Vyi 20 m s Solving For h Vyo 0 m s the subscript o represents the peak point of the ball we will use this as Vyf Ay g g 9 8 m s2 yi 0m yf h The kinematics equation needed Vyf 2 Vyi 2 2ay y Plug givens 0 m s 2 20 m s 2 2 9 8 m s2 h 0 m2 s2 400 m2 s2 19 6 m s2 h 400 m2 s2 19 6 m s2 h 20 4 m h The ball reaches a maximum height of 20 4 meters
View Full Document
Unlocking...