Q: These neodymium magnets are pretty strong. How do you separate them?
A: They can usually be separated by hand one at a time by sliding the end magnet off the stack. If you cannot separate them this way, try using the edge of a table or a countertop. Place the magnets on a tabletop with one of the magnets hanging over the edge. Then, using your body weight, hold the stack of magnets on the table and push down with the palm of your hand on the magnet hanging over the edge. With a little work and practice, you should be able to slide the magnets apart. Just be careful that they do not snap back together once you have separated them.
Q: The tape holding the magnets to the wooden dowel broke or came off. How can I prevent that?
A: The tape could be breaking for a few reasons. First, the stress of pulling a ball bearing off the magnets might sometimes be enough to break the tape. Second, the force of a ball bearing hitting the magnet might occasionally be strong enough to break or detach the tape. Third, if the magnets are too close together, then the attraction between magnets might be strong enough to break the tape. The third scenario is unlikely with a single-magnet stage Gauss rifle.
Single-Magnet Stage Rifle. If the tape broke while you were working with a single-magnet stage Gauss rifle, then it was probably from the stress of adjusting or resetting the ball bearings. Try reinforcing the tape by adding a second (or even a third) layer of tape to secure the magnets to the dowels. You can also use a longer piece of tape to wrap completely around the dowels and magnets. In addition, you can reduce the stress on the tape by sliding the ball bearings off the magnets, instead of pulling them straight off. Another way to decrease the stress on the tape is to hold the magnet with one hand while you remove and replace the ball bearings with the other hand.
Multi-Magnet Stage Rifle. If the tape broke while you were working with a multi-stage Gauss rifle, think about when the tape broke. Did it break while you were setting or resetting the Gauss rifle? Or did the tape break suddenly when you were not handling the rifle?
- It broke while I was setting or resetting the Gauss rifle. If the tape broke while you were setting or resetting the rifle, then it was probably from the stress of adjusting or moving the ball bearings. Try reinforcing the tape by adding a second (or even a third) layer of tape to secure the magnets to the dowels. You can also use a longer piece of tape to wrap all the way around the dowels and magnets. In addition, you can decrease the stress on the tape by sliding ball bearings off the magnets, instead of pulling them straight off. Another way to decrease the stress on the tape is to hold the magnet with one hand while you remove and replace the ball bearings with the other hand.
- It broke suddenly while the Gauss rifle was resting on the table. If the tape broke suddenly while the rifle was resting on the table, then the problem might be that the magnets are too close together, especially if they snapped together after the tape broke. Check to make sure the magnets are the correct distance apart (10 cm; see Figure 4 in the Experimental Procedure). If they are 10 cm away from each other, but you still have this problem, move the magnets slightly farther apart, retape them (using a couple of layers of tape for added strength), and try the experiment again.
Q: The tape is not breaking, but the magnets are slipping out of the tape. What can I do to stop that?
A: This is due to the same factors as in the problems described in question number 2. Try the troubleshooting steps and techniques discussed in that section.
Q: The magnet stages in my multi-stage Gauss rifle are so attracted to each other that they stick together before I can tape them in place. What can I do about this?
A: The magnets will be attracted to each other if they are placed too close together. Make sure that your magnet stages are the correct distance (10 cm) apart (see Figure 4 in the Experimental Procedure). If the magnets are 10 cm apart but you still have problems with them coming together before you can tape them in place, gradually increase the space between each of the magnets until they stay where you put them. Whatever spacing you settle on, put the same amount of space between all the magnet stages in your Gauss rifle.
Q: The trigger ball rolls toward the magnet stage and fires the rifle before I can lift the slide. How do I stop this?
A: The trigger ball will roll to the magnet before you can lift the slide if the trigger ball and magnet are too close together. Make sure the trigger ball is the correct distance (5 cm) behind the magnet (see Figure 2 in the Experimental Procedure). If the trigger ball is 5 cm away from the magnet and you still have this problem, try increasing the space between the trigger ball and magnet until the ball stays in place. Measure this distance, and use this same spacing each time you fire the Gauss rifle.
Q: The launched ball bearing rolls, bounces, slides, or moves around after it lands in the sand. If this happens, where should I start measuring the horizontal distance traveled by the ball bearing?
A: Measure the horizontal distance from the edge of the table to where the ball bearing first hits the sand, not the location where the ball bearing comes to rest. See Figure 3 in the Experimental Procedure.
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