PURPOSE: To demonstrate the independence of velocity components in a counterintuitive way.
DESCRIPTION: A ball is placed in the funnel and the funnel cocked by compressing a spring. The track is raised at one end so that when it is released the cart accelerates down the track. At a certain point a bump below the track trips a lever, releasing the spring and ejecting the ball perpendicular to the track.
Before doing the experiment, ask your students where the ball will fall: in front, behind, or in the funnel.
SUGGESTIONS: Precede this demonstration with C2-25: FUNNEL CART,and C2-26: FUNNEL CART WITH MASS OVER PULLEY, to set up your students for this problem.
REFERENCES: (PIRA 1D60.15) See Demonstration Reference File for derivation of equations as well as papers describing uses for and variations of this apparatus.
EQUIPMENT: Funnel cart with ball on tilted track, as photographed.
SETUP TIME: None.
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