What is the Speed of the Package at Maximum Height?

[D H]

It often helps to draw pictures. But yes, the angle between the radial and velocity vectors would be 39 degrees at launch. What is the angle going to be at the maximum altitude?

Think about it, sketch some pictures. It might help to bring the picture a bit closer to Earth. For example, imagine a baseball thrown from center field to home. At the top of the baseball's arc, what is the angle between the ball's velocity vector and local vertical?

 

[mybrohshi5]

Isnt it 90 degrees because at the top of the arc (or maximum altitute) there is only velocity in the horizontal direction and none in the vertical?

 

[D H]

Correct.

What's next? Can you finish this problem now?

 

[mybrohshi5]

Yes that helps. I am going to rework the problem this weekend when i am studying for my test and if i run into any problems i will post here again.

Thank you for all the help.