Question

attachment below:

i need to understand this

Answer 1

I need help understanding it too. Is it a drawing of a projectile being shot up? If so, I suspect that they want you to use trigonometry to calculate the line segment from D to E. This would give you the distance that it takes to fall to the ground? Knowing the distance, you can calculate the time it takes to hit the ground using d = 1/2 at^2. Where 'a' is the gravitational constant of acceleration, 9.8 m/s^2. You would multiply that times two to get the total time of flight. If the point 'D' is NOT at the top of the path of the projectile, you can still figure it out by using trigonometry to calculate the vertical component of the velocity. It is the vertical part, the part in the y direction that will tell you how long it will take for the projectile to rise and how long it will take it to fall. Remember when looking at projectiles the vertical and horizontal portions are independent of each other.

Answer 2

You can also solve similar types of problems where they give you the total horizontal distance by breaking up the velocity into its components and using the horizontal component to solve the problem.

Answer 3

I have already three solutions for this one XD
also, i cannot use d = 1/2 at^2 because Vi is not equal to zero
but i found the best solution and easiest solution for this one!
thanks for your time ;p