## Introduction: Physics Marble Canon Project 2018

Want to build your own marble cannon?

Here's how!

## Step 1: Materials

-2 springs

-2 bolts

-2 wings nuts

-1 washer (all #10-24)

-hot glue, wood glue, and prayers

-2 1/2 in. and 1/2 in. wood screws

-a pair of metal pipe collars

-4 discount rack white cedar boards of 1x4s

-10 ft. 1.5 in. wide PVC pipe (cut down)

- 2x2 sq ft board of plywood

## Step 2: Build a Base

## Step 3: Build a Protactor

This will help you to adjust launch angle and get more accurate and precise results

## 3 Discussions

I calculate differently:

the only motion which has acceleration is in y direction and in x direction we have a motion without acceleration so for case #1 we have in Metric units:

0.25 = - 0.5*9.8*t^2 + V0*sin(15)*t ..... y direction

4 = V0*cos(15)*t ..... x direction

So : t = 4/(V0*cos(15))

By substituting t from second equation in to the first equation we have:

-0.5 *9.8*(4/(V0*cos(15))^2 + V0*sin(15)*4/(V0*cos(15)) = 0.25

V0 = sqrt(8*9.8/(4*sin(15)*cos(15)-0.25*cos(15)^2))

V0 = 10 m/s

Is there a step missing? When the PC is attached to the protractor, there is something inside the PVC. How does one make that part?

What a cool project and I love the science behind it! Great job!