The Mom I Want to Be

AGES: Seven to 12

 

Build a catapult to test the relationship between the angle of release and the distance traveled by a catapulted object – a 2d vector.  Two-dimensional vectors are diagrammatically represented as two arrows beginning from the same point, one traveling horizontally and the other vertically. They offer a way to organize information about how objects move through space.

 

Wood block, 2 by 2 inches

Paint stick or wooden ruler

Plastic spoon

Plastic mailing tape

Marshmallows

Pencil and paper

Protractor

 

Construct your catapult by placing the wooden block flush with the top of the paint stick. Then lay the handle of the spoon on top of the wooden block with the bowl of the spoon extended over the paint stick. Again, the spoon handle should be flush with the edge of the block. Lash the three pieces together with plastic mailing tape. Place the free end of the paint stick next to the wall. Load the marshmallow in the spoon, pull it down as close as you can to the paint stick and prepare for liftoff. Release the spoon and watch your marshmallow soar. Then measure the distance from the wall to where it lands. This is the distance covered using a 90-degree angle. Record your distance and angle on a sheet of paper. Now use the protractor to measure 10 degrees off the floor. Lift the end of the ruler to that height. Reload your spoon, release and record the distance using an 80-degree angle. Repeat this procedure for different heights. Then review your written results and figure out which angle worked best.