上海交通大学：《工程学导论》课程教学资源（讲义）Instructions：Building an Index Card Tower

Instructions:Building an Index Card Tower Michael Parr The following are instructions for building a tower that is able to hold a one-pound jar at least 39 cm in the air,and is made only out of tape and as few index cards as possible. Equipment: Index Cards (20) Scissors (1 pair) ）Tape (1 roll) Ruler(1) 1.Construct the main legs la)Cut one index card in half,parallel to the lines so it will still be the full length.See Fig I 1b)Curl each half into a long tube.Have the card's edges overlap approximately 1 cm.Place two small pieces of tape on the overlapped section,one near the top and one near the bottom,to secure the shape.See Fig II 1c)Repeat steps la)and 1b)until you have three legs,each at least 40 cm long. 2.Construct the supports 2a)Cut two index cards in half along the length,as in step la).See Fig I 2b)Curl three of the cards cut in step 2a)into tubes,preserving the length as in step 1b).Again, place tape over a 1 cm overlap at the top and bottom.See Fig Il 3.Create the platform 3a)Place two index cards down on the table,one on top of the other.Adjust the index cards so one is still partially covering the other,but the two together make a square.Tape across the middle of the overlap on each side.Also tape along the outside edges where the two cards overlap.This is the square base.See Fig IlI 3b)Place the main legs on top of the square base.Put one leg 0.5 cm away from the very center of one edge.Put the other legs and equal distance apart from the first leg,but also 0.5 cm from the opposite edge.Be sure that the distance between all the legs is equal and each is about 0.5 cm away from the edge of the square base.Tape the legs in place.See Fig IV 3c)Place each of the three supports such that one end is touching the center of the square,and the opposite end rests against one of the legs.Secure this orientation by taping both ends of each support.See Fig V 4.Prepare the tower for testing 4a)Turn the tower upside down,so the square base is up in the air.The square base is the platform on which the weight will rest. 4b)Check to see that all the taped portions are secure and the tower will remain steady. 4c)If the tower bows outward,cut one index card in half.Use these two halves,along with the half remaining from step 2,to secure the tower:connect each leg with the others by taping each end of the index card to one leg,roughly halfway up,until all the legs are connected. See Fig VI 0.5em Fig I:Cut Fig II: Fig III: Fig IV:Position Fig V:Add a Fig VI:Final Curl &Tape Overlap the legs Support Structure Tape

Instructions: Building an Index Card Tower Michael Parr The following are instructions for building a tower that is able to hold a one-pound jar at least 39 cm in the air, and is made only out of tape and as few index cards as possible. Equipment: Index Cards (20) Scissors (1 pair) Tape (1 roll) Ruler (1) 1. Construct the main legs 1a) Cut one index card in half, parallel to the lines so it will still be the full length. See Fig I 1b) Curl each half into a long tube. Have the card’s edges overlap approximately 1 cm. Place two small pieces of tape on the overlapped section, one near the top and one near the bottom, to secure the shape. See Fig II 1c) Repeat steps 1a) and 1b) until you have three legs, each at least 40 cm long. 2. Construct the supports 2a) Cut two index cards in half along the length, as in step 1a). See Fig I 2b) Curl three of the cards cut in step 2a) into tubes, preserving the length as in step 1b). Again, place tape over a 1 cm overlap at the top and bottom. See Fig II 3. Create the platform 3a) Place two index cards down on the table, one on top of the other. Adjust the index cards so one is still partially covering the other, but the two together make a square. Tape across the middle of the overlap on each side. Also tape along the outside edges where the two cards overlap. This is the square base. See Fig III 3b) Place the main legs on top of the square base. Put one leg 0.5 cm away from the very center of one edge. Put the other legs and equal distance apart from the first leg, but also 0.5 cm from the opposite edge. Be sure that the distance between all the legs is equal and each is about 0.5 cm away from the edge of the square base. Tape the legs in place. See Fig IV 3c) Place each of the three supports such that one end is touching the center of the square, and the opposite end rests against one of the legs. Secure this orientation by taping both ends of each support. See Fig V 4. Prepare the tower for testing 4a) Turn the tower upside down, so the square base is up in the air. The square base is the platform on which the weight will rest. 4b) Check to see that all the taped portions are secure and the tower will remain steady. 4c) If the tower bows outward, cut one index card in half. Use these two halves, along with the half remaining from step 2, to secure the tower: connect each leg with the others by taping each end of the index card to one leg, roughly halfway up, until all the legs are connected. See Fig VI Fig I: Cut Fig II: Curl &Tape Fig III: Fig IV: Position Overlap & the legs Tape Fig V: Add a Fig VI: Final Support Structure