The x axis of a trajectory represents its ____________.

Height in the vertical direction.
Displacement in the horizontal direction(my guess)
Longitude
Latitude

A person throws a rock horizontally off a cliff ata a speed of 9 m/s from a point 64.8 m above the ground. How long is the rock in the air?
13.2 s
26.4 s
3.64 s
5.14 s

A package falls from an airplane in level flight at constant speed. If air resistance can be neglected, how does the motion of the package look to the pilot.
The package appears to travel in the shape of a parabola.
The package appears to fall straight downward.
The package appears to travel backward.
The package appears to fall backward and downward.

A paintball is shot horizontally in the positive x direction. At time Trianglet after the ball is shot, it is 4 cm to the right and 4cm below it’s starting point. At time 2trianglet, what is the position of the ball relative to it’s starting point. Ignore air resistance.
12 cm to the right and 16 cm below
8cm to the right and 8 cm below
12 cm to the right and 8 cm below
8 cm to the right and 16 cm below

Please help me solve and give correct answers!

6 answers

1st guess is good ... others?
I don’t have any more guesses... these are very hard and I can’t even get an answer close enough to any answer choices :(
But i guess for 2 I choose C., 3 I choose d and 4 B
2nd ... horizontal velocity is not a factor
... how long to fall from 64.8 m? ... gravitational acceleration

3rd ... package maintains same horizontal speed as plane

4th ... horizontal velocity is constant , vertical is accelerated by gravity
... horizontal displacement is vs. t , vertical displacement is vs. t^2
Can you just give me the answers? This is confusing and I still have no idea.
2nd ... h = 1/2 g t^2 ... 64.8 = 4.9 * t^2

3rd ... package stays in same horizontal position relative to plane
... pilot sees it drop straight down

4th ... the time is doubled
... so horizontal is doubled , and vertical is quadrupled (doubled squared)