  # labview1958

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1. Do you intend to pass an AC current through the coil? If it is for short duration, the temperature rise would be minimal.
2. Maybe I am using the Hall probe to measure magnetic force wrongly. Should I put the tip or the long side of the probe on the magnet surface?
3. Does it mean that Br of a magnet is actually the theoritical B in the centre of a magnet? The B on the surface of a magnet is about half of the Br, for all configurations of a magnet? Where can I find the proof?
4. "In a conventional magnet with an air gap, there is a well-known end effect which may be described by saying that the effective length of the magnet is larger than the physical length by an amount which is roughly equal to the air gap." I got this from a journal. How does a conventional magnet have an air gap?
5. When a magnet moves over an aluminium sheet, it causes eddy current in it. This causes repulsion force between the magnet and it's image in the aluminium sheet. Which configuration causes the most force? This is all about MAGLEV.
6. Does anyone know what is the meaning of "ignoring magnet edge and end effects"?
7. Let's say a magnet is moving with a velocity, v , over an aluminium "roadbed". Which configuration would give a stronger repulsion force: a. The shorter dimension in the direction o0f motion or b. The longer dimension in the direction of motion. C. both give a same force.
8. Which dimension short or long of the magnet is in the direction of motion.
9. I have another problem about excel staight line graphs. The error bar in the y-axis is 0.0002 and the x-axis is 0.2. Does the slope of my graph have an error of 0.0002/0.2 = 0.001 ? Is that a fair assumption?
10. I am using microsoft excel program to draw the best fit linear line. It gives R^2 = 0.90. I understand the complete 100% fit would give R^2 = 1.0. How do I get my error from here?
11. I am measuring repulsive force between two magnets. The distance is moved by a stepper with steps of 0.0254 mm per step. The electronic balance measures force with a accuracy of 0.0001g.
12. Let's say the Br of a magnet is 1.23 Tesla. If I put my probe touching the magnet, it reads 0.6 Tesla. is there something wrong? Does it mean Br of 1.23 Tesla is equivalent to 0.6 with a probe?
13. I have a graph of Force(mN) vs Distance(m). The error in the force is 0.0001g and the error in the distance is 0.0254mm. I have 10 points on the graph. Excel gives R^2 = 0.90. My gradient is 1.045. What is it's error? Can someone help?
14. I have a brand new bar magnet rated as 1.23 Tesla by the manufacturer. However when I measured it with a meter, it gave a reading of 0.61 Tesl. Why?
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