Question

Prof. Dink is having a nightmare where she finds herself snowboarding! She is moving horizontally when she rides over a cliff that is 3.14 meters high. She lands a horizontal distance of 3.20 meters away (from the base of the cliff). How fast was she moving when she went over the edge of the cliff? [Assume the laws of physics are the same even in her dreams!]

Answer 1

From Kinematic equation

Y=Y_o+V_oyt-(1/2)gt²

when object hits ground Y=0 and initial Vertical Velocity is zero i.e V_fy=0

0=3.14+0-(1/2)(9.81)t²

t = sqrt[2*3.14/9.81]

t=0.8 s

Horizontal Distance traveled is

D=V_oxt

3.2 = V_ox(0.8)

V_ox=4 m/s

Initial speed of dink is

V_o= 4 m/s