Question

A rock is thrown horizontally with a speed of 20 m/s from a vertical cliff of height 25 m.

What is the velocity (magnitude and direction counterclockwise from the +x-axis, which is the initial horizontal direction in which the rock was thrown) of the rock just before it hits the ground?

Magnitude -

Direction - degrees

Answer 1

Inbal speed u= 20 m/sec LA. thoon horiz antally ince vock is ori antal u 20 msec acc elaration 0旱 @tavity is sec. As ㅓhe Yock falls down to earth, the YeYKcal displacement is Sy.h -25 m. antal direction , V.U' +Zombec . Since there is no accelerahon in hom; antal divechon , Yn=4=tZom Nos applying the kinemakes brmula uas in Verkcal divect on V 490 t 22.136 m/sec z) Since v is directed downward V -22.136 m/sec gon tal valcity M3 +V 2031.136) ) The magni tuda = 20 + (-22.136 つ|V= 29.83 m/sec tan/-22.13 2D の7he direction of 유nal veloch is θ= tan'(Ma nal Ve loc V.