Marble Launcher Lab

Home » StickMan Physics » Unit 2: Two Dimensional Motion: Projectile and Non-Projectile » Marble Launcher Lab

Follow my intro video as we figure out the barrel velocity of the marble launcher. Then challenge yourself to more questions.

Marble Launcher Part 1:

Finding Barrel Velocity

To start off the lab we must figure out the velocity of the marble launcher on the third setting where we will be firing the marble from. (See how the marble launcher spring is in the third groove in the picture)

Question we need to answer for part 1:

How fast is the marble launchers barrel velocity on setting three?

To do this we first calculated the height the marble was launched from.

Next we fired the marble horizontally and measured the distance downrange it landed.

Creating an Independent X and Y-Axis Givens List

To determine horizontal velocity we create a separate givens list.

Y-Axis Information

Height is 1.168 m which the marble will fall down from
Initial y-velocity is 0 m/s
Acceleration due to gravity is 10 m/s² down

X-Axis Information

Distance downrange the marble landed is 2.287 m

We used Y-Axis information to solve for time:

Note: this equation below can only be used to solve for time when the initial Y-Axis velocity is 0 m/s, which it was in our first step.

Then we used X-Axis information to solve for horizontal velocity:

Marble Launcher Part 2:

Horizontal Shot Challenge

Now that we know the barrel velocity we are ready to move on to the second part challenge

Question we need to answer for part 2:

How far downrange will the marble land with a barrel velocity of 4.73 m/s if shot horizontally from 1.575 meters up?

Since we have a new height, we need to solve for a new time to fall
With a new time to fall we can solve for the new distance downrange (X) the marble will land

X is now the new location to place a target downrange, in a lab setting you will set up a target. To check your answer you would attempt to hit the target.

Marble Launcher Part 3:

Angular Shot Challenge

Question we need to answer for part 3:

How far downrange will the marble land with a barrel velocity of 4.73 m/s if shot at 35º?

You can't use the shortened equation to solve for time falling from a height since the vertical velocity is no longer zero.

Use this section as a reminder on how to solve for time when a projectile does have an initial vertical velocity and lands at the same height

X is now the new location to place a target downrange, in a lab setting. After setting up the target, you would check your answer by attempting to hit it. In this example, the target should be at the same height at the marble launcher barrel. You need to place the target on something keeping it the same height at the initial launch height. (Y = 0 meters)