NGSS Gravity and Orbit Lab MS-PS2-4

This is a 2-day lab where students investigate how increasing distance from the sun affect revolution period. (Can also change the mass of the planet or sun for an extension.)

Materials Needed:

· Fishing line (about 20 meters)

· Short metal tube (sturdy straws can substitute)

· Rubber stopper with hole (cork can substitute)’

· 50 g mass (metal washers can substitute)

· Sharpie

· Meter stick

The rubber stopper is swung in a circle above your head while the mass pulls the stopper inward toward your hand. When the stopper is swung around at the right speed, the inertia of the stopper equals the acceleration of gravity toward your hand and remains in equilibrium (not moving closer or further away from your hand). Students then change the length of the string and see how it affects the period of revolution.