Projectile Motion Help: Calculating Direction of a Ball Thrown from a Cliff

[naimagul]

Homework Statement

a ball is throwm horizontally from top of a cliff with velocity 10meter per second. height of cliff above the ground is 45 meters. calculate the direction of ball to horizontal surface just before it hits the grouND

The Attempt at a Solution

i found time=3s...and horizontal distance as 20m...but i cud not figure out ANYTHING ABT THE DIRECTION...PLZ HELP

 

[ideasrule]

Do you know how to get the vertical and horizontal components of the ball's velocity right before it hits the ground? If so, you can directly use trigonometry to get the direction.

 

[naimagul]

um i have tried a lot... can u please help me find the angle just before the angle hits the horizontal surface...m a learner...looking forward to ur cooperation

 

[ideasrule]

Gravity acts downwards, so it can't change the ball's horizontal speed. It's still 10 m/s on impact. As for vertical speed, can you find a kinematic equation that relates acceleration, distance traveled, initial speed, and final speed?

 

[naimagul]

Gravity acts downwards, so it can't change the ball's horizontal speed. It's still 10 m/s on impact. As for vertical speed, can you find a kinematic equation that relates acceleration, distance traveled, initial speed, and final speed?

yes v²-u²=2as...where a is acceleration
u is initial velocity...s is distance...v is final velocity