Action Centers

Gear Up For S.T.E.M.

When your den/patrol/crew visits the S.T.E.M. Action Center, you will have an opportunity to engage in activities that involved some of the basic principles in the important areas of Science, Technology, Engineering and Math. Come and have some fun!

Materials Needed: None

How It Works: As you visit the other Action Centers, you will find that S.T.E.M. principles play a role in everything that we do. Properties like friction, propulsion, potential and kinetic energy and more are crucial to so many of the activities that we take for granted. Learn about the science behind your activities in the write-ups below and while you are visiting each Action Center.

Gear Up For Climbing

At the Rock Climbing Action Center, the members of your den/patrol/crew will be able to experience climbing on a tower under the supervision of trained climbing instructors. The bouldering wall will also be available to test your agility. Please note that there is a weight limit of 250 lbs for this activity.

How It Works: Climbing is a tug of war between the forces of gravity and friction. To succeed in climbing, you don’t need pure strength; you need to learn how to hold on to the rock in such a way to maximize the friction between your hands and feet and the rock. This will take the load off your arms.

Friction is also important in belaying. It is friction between the rope and the device that reduces the force on a belayer’s arm. This is the key to allowing a smaller climber to safely belay a larger climber.

Learn more about the physics of climbing.

Gear Up For Rockets

At the Rockets Action Center, your den/patrol/crew will have an opportunity to try your hand at launching a water bottle rocket that you have built to see how well you understand the principles of rocketry. There are many designs that are possible to construct a rocket using a two-liter soda bottle. The basic design is in the figure below. The Internet can give you details about how to construct your rocket. Bring your rocket to MassJam 2018 ready to go. We will have materials available if any last minute repairs are needed. The MassJam staff reserves the right to reject any rocket that is deemed unsafe (for example, sharp objects attached to the nose cone will not be allowed).

Materials Needed: One complete 2-liter soda bottle rocket, ready to launch.

How It Works: There are two major principles involved in successful rocket launch: thrust and guidance. Water bottle rockets are a fun way to see these principles in action.

Thrust: Filling the bottle partially with water and then pressurizing the air in the bottle causes the water to be expelled out of the nozzle at high speed causing the rocket to shoot upward.

Guidance: The nose cone reduces air resistance and the fins provide stability.

Learn more about the physics of water bottle rockets

Gear Up For The Obstacle Course

At the Obstacle Course Action Center you will be running, jumping and climbing over and through obstacles.  Your patrol or crew will be challenged to make it through an obstacle course in speedy time.  In addition to teamwork, physics will play an important role in your success.

How It Works: Obstacles, running and moment invoke friction and momentum. The climbing wall discussed friction.  For this lesson, we will focus on running.  Newton’s 1st law concerns moving objects and states that object in motion tend to stay in motion, objects at rest tend to stay at rest, unless acted upon by an external force.  If forces are balanced, an object won’t move.

Running:  When you start running have you noticed that it takes an enormous burst to go from being still to running?   Have you ever been running and tried to take an abrupt turn?  Your body wants to keep moving forward.  Going from still to moving, or turning abruptly takes a lot of force. These are examples of Netwon’s 1st law.

Try it:  Stand still and start running.  Once you are running take an abrupt turn.  When you are on the obstacle course notice how motion can help or hinder you.

Learn more about the physics of motion.

Gear Up For Tomahawks

At the Tomahawk Action Center your patrol/crew will be given a chance to throw three tomahawks. How well can you do this? Can you get the tomahawk to hit the center of the gear targets? Come and see!

How It Works: There are three major forces that play a role when throwing a tomahawk. Static friction is present when you hold the tomahawk and is a key in keeping your back foot steady as your make your throw. Your front foot uses sliding friction to keep it from accelerating forward along the ground. Air resistance can alter the speed at which the tomahawk travels. The harder you throw it, the more air resistance will be present, acting to slow the tomahawk down.

How hard should you throw the tomahawk? That will depend on how far away you are from the target. The further away you are, the harder the throw you need to ensure the tomahawk completes a full rotation of the blade.

Learn more about the physics of tomahawk throwing.

Gear Up For Geocaching

At the Geocaching Action Center your den/patrol/crew will be challenged to locate some caches around the camp area.

Materials Needed: If you have access to a GPS unit, please bring it with you. If not, don’t worry, one will be provided for you to use.

How It Works: A network of about 30 satellites orbit the Earth and at least four of these GPS satellites are ‘visible’ at any time from your location. Your GPS unit listens for these satellites and determines how far away from each one you are. This creates overlapping spheres on which you are located. By finding the intersection of these spheres, the GPS unit can determine your location, usually within a few yards. The more satellites that are visible, the more accurately your position can be determined.

Learn more about how GPS works.

Gear Up For Archery

At the Archery Action Center, each member of your den/patrol/crew will have an opportunity to test your ability with the bow and arrow.

How It Works: Both the bow and the arrow contribute to how an arrow flies through the air.

Bow: When you draw back on the string, you are changing the shape of the bow, giving potential energy to the bow. This then acts as a spring turning the potential energy into kinetic energy which is transferred to the arrow when you release the string.

Arrow: When the arrow is released from the string, the arrow actually begins to oscillate back and forth. This oscillation is key to the trajectory that the arrow follows when fired.

Learn more about the science involved in archery.

Gear Up For Rifles

At the Rifle Action Center each member of your den/patrol/crew will have a chance to test your skill with an air rifle.

How It Works: There are two important principles at work with an air rifle: propulsion and trajectory.

Propulsion: Propulsion in an air rifle is achieved by compressing a pocket of air behind the pellet. There are different methods of compressing the air (spring-piston, pump pneumatic and others). When the trigger is pulled, it releases the elastic potential energy that is stored in the air. The pellet is then expelled from the chamber down the barrel of the rifle by the expanding column of pressurized air.

Trajectory: It is important to understand that a pellet (or other projectile) does not travel in a straight line but rather in a parabola. As the pellet leaves the muzzle, gravity starts to act, bringing the path of the pellet downward. This is particularly important when sighting a rifle. A properly sighted rifle will allow the bullet trajectory to drop and intersect the line of sight at the target.

Learn more about how air rifles work.

Gear Up For Sports

At the Sports Action Center you will get a chance to challenge other dens/patrol/crews to friendly competition on the human foosball court or in one of our GaGa ball pits.

How It Works: In both of these sports, the main action is hitting or kicking a ball. What happens when you strike the ball involves both Newton’s third law of motion and the concept of elastic and inelastic collisions.

Newton’s Third Law of Motion: You may already be familiar with this law which, simply put, states that for every action, there is an equal and opposite reaction. You see this when you hit or kick the ball which then moves away from your foot in the opposite direction. Forces always act in pairs, so striking the ball forces it to move away from your hand or foot.

Elastic and Inelastic Collisions: An elastic collision is one in which there is no loss of kinetic energy in the collision. An inelastic collision is one in which part of the kinetic energy is changed to some other form of energy. Most collisions are neither completely elastic nor inelastic. When you hit or strike the ball, for example, some of the energy is converted to sound so that kinetic energy is not conserved.

Learn what happens when you kick a ball.

Learn more about the physics of motion.