The problem that I choose is a problem of motion in 2-dimension, so I’m going to use kinematics equations and other basic math formulas. Note: the air friction is neglected in the problem, “i” stands for initial and “f” stands for final.

A stone is thrown from the top of a building upward at an angle of 30.0° to the horizontal with an initial speed of 20.0m/s. If the height of the building is 45.0m,

Diagram of the problem from working model 2D

A)How long does it take the stone to reach the ground? We need to find the component velocity, so to do that we use component equation which is?
Solution
Diagram for the solution from working model 2D

B)What is the speed of the stone just before it strikes ground?
Solution
Diagram for the solution from working model 2D