A hockey puck slides off the edge of a table with an initial velocity of 20.0 m/s. The height of the table above the ground is 2.00 m. How far from the edge of the table, measured along the floor, does the puck hit the floor?
A) 20.0 m
B) 40.0 m
C) 12.8 m
D) 19.6 m
E) 6.4 m

Question

Quizplus · Accepted Answer

The puck has an initial vertical velocity of 0 m/s and an initial horizontal velocity of 20.0 m/s. The time it takes for the puck to hit the floor is:$$t = \sqrt{\frac{2h}{g}} = \sqrt{\frac{2(2.00 	ext{ m})}{9.81 	ext{ m/s}^2}} = 0.636 	ext{ s}$$The horizontal distance the puck travels before hitting the floor is:$$d = vt = (20.0 	ext{ m/s})(0.636 	ext{ s}) = 12.8 	ext{ m}$$

A Hockey Puck Slides Off the Edge of a Table