Dry Ice in Circular Motion (Stephen)

Author

Stephen

Principles

Newton's 2nd Law

Uniform Circular Motion

Standards

HS-PS2-1.

Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration

Materials needed

• dry ice

• smooth surface

• thread

• tape

• screw

• screw driver

Procedure

• Place a screw into a piece of dry ice.

• Tie a piece of thread around the screw and tape the other end of the thread to the center of the circular path that you want the dry ice to follow.

• Push the dry ice tangent to the circular path.

Explanation

• Objects accelerate in the direction of the total force vector.

• To get an object to turn, and total force must be acting in the direction that the object turns.

• The total force acting on the dry ice points towards the center of its circular path in the "centripetal" direction.

Questions

• What would happen if the string broke while the dry ice was following the circular path?

• How would increasing the mass of the dry ice affect the tension required if the the orbital period remained constant?

• What direction does the thread pull the dry ice?

• How is this demonstration similar to how the earth orbits the sun?

Everyday examples of the principles illustrated

• making a turn in a vehicle

• satellites

• orbits around the sun

Movies

References

HyperPhysics -Circular Motion