Instruction Guide: Faraday Golfing Machine

Soccer/Golf Attachment

Have students build the soccer/golf attachment from their NXT kit instructions  (9797 Manual, p.50).

Have students take notice of the following:

• The instructions contain no words; ask students why? (same instructions used in many countries/languages).
• The shaded blue box lists all the parts needed for the next step:
  • To improve building efficiency, have one student find the next parts, the second student complete the building steps and then the first student check the built product versus the illustration before advancing to the next step.
  • Have students switch roles every page, so both students get practice building
• A full scale illustration of each axle and the longer beams are included on each page to verify the component size before beginning construction
• On newer kits (9797, version 95), the inside of the manual front cover contains an illustration of the components which have changed shape or color from the original 9797 kit (version 46).  The construction illustrations represent the original kit components, so students using the new version 95 kit may be confused by discrepancies between the illustrations and the components in their kits.

Faraday Golf Tournament

Use this Faraday Golf Tournament PPT to explain the challenge and its scientific underpinnings.

Slide 1

• Students begin with the Golfing Attachment which they just completed.
• They will then need to build a self-supporting frame/structure to support this attachment with a size/height sufficient to allow it to strike an NXT red or blue ball on a tee
  • a roll of tape makes a great tee
  • have student recall the lesson previous lesson on building strong structures
• Finally, they will need to build a remote control to operate their Golfing Machine. This control will take advantage of Faraday's Law to eliminate the need for a batteries.

Slide 2  

• The illustration shows the inside of an NXT motor with its internally gearing.
• The photo shows the round metal motor that drives the gears.
• Have students connect soccer attachment motor directly to a second motor using a wire:
  • The second motor will act as a generator and creating an electric current that cause the soccer/golf attachment to move. The is the Faraday Principle at work (named after Michael Faraday, the scientist, not Daniel Faraday, the character on "Lost")
  • A light cable and lamp can be attached to a lone motor to demonstrate for students how the motor can act as a generator by turning the orange hub and watching the lamp illuminate.
• In the case of the Golfing Attachment motor, electrical energy (current in the wires) is converted into kinetic energy (motion)
  • The Electromagnet link show an photo and illustration of a simple electromagnet using a battery, loops of wire and an iron nail:
    • Ask students if they have built an electromagnet like this in early science classes
  • The Motor Animation link shows a video animation of how motor works. An outer fixed magnet (blue) creates a constant magnetic filed between its north and south poles. An inner rotating electromagnet (green battery, yellow loop of wire) also produces a magnet filed which turns the loop in an attempt to align with the N/S field of the fixed magnet. However, just when the fields are nearly aligned, the direction of the current through the loop reverses (red line on yellow loop base), so the electromagnet field also reverse and rotating loop attempts to align in the opposite direction. By constantly switching the direction of the current every half-turn, the motor turns constantly as it "chases" the fixed magnet field.

Slide 3  

• Michael Faraday discovered that above process could be reversed.
• In the case of the remote control generator, Faraday's Law converts kinetic energy (motion) into electrical energy (current)
  • The Faraday's Law Animation link goes to an interactive animation site. The user can click on the bar magnet and move it through the loops of wire. When this happens, a current is generated in the wire as can be seen by the meter moving and the lamp illuminating.
    • the lamp will illuminate when the magnet is move in either direction, but the mete shows the current actually switching direction with the movement
    • note too, that the intensity of the light and the level shown on the meter increase with the speed at which the magnet is moved through the loop
  • The Motor vs Generator Animation link is a video which shows the similarities and differences between eletrcial motors and generators. Here again, we have and outer fixed magnet and an inner rotating electromagnet. In the case of the generator however, the mechanical energy is input (wind in the case of the video, but is could also be a hand crank, etc.) on the rotating electromagnet and electricity is produced in the wire loop.
• Have students build an handle of their choice onto the orange hub of a second motor (turning this handle/hub will cause the soccer/golf attachment to “swing”. Be sure to attach the crank to the orange hub with more than a single axle (use some of the four round connector points on the orange hub) or else the force of turning the crank may bend/damage the lone axle.    

Faraday Golf Tournament Rules

• Build ramp with a tee (roll of tape) on a flat surface at the bottom, and another flat surface beyond the top edge of the ramp. Create a hole-in-one target area on the flat surface beyond the ramp.
• A Task Assignment sheet for this challenge is included in the Summative Assessment.
• A Driving Range competition can also be added where teams see how far they can hit the ball on a carpeted floor.