This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ...the influence of the magnetism is estimated on this assumption, so that if the poles are located elsewhere an error will result. Suppose, for example, in the needle represented in the preceding figure its N and S magnetic poles, instead of being located at its extremities N and S, are situated at N' and S'. In other ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1908 Excerpt: ...the influence of the magnetism is estimated on this assumption, so that if the poles are located elsewhere an error will result. Suppose, for example, in the needle represented in the preceding figure its N and S magnetic poles, instead of being located at its extremities N and S, are situated at N' and S'. In other words, instead of lying in the direction of the line NS, they lie in the direction of N'S'. Then, while the north pole of the needle is in reality pointing towards 28 on the scale shown in the figure, it appears to he pointing to 31, thus causing a serious error of 3. The magnetisation of a needle obtained by stroking it from end to end with a single magnet pole is known as "magnetisation by single touch." This method is not apt to bring the opposite poles exactly at the extreme ends of the needle. Sometimes, in magnetisation by single touch, the needle is magnetised by rubbing one pole of the magnetising magnet against one end of the needle, and the other pole against its other end. Perhaps, however, the best method of magnetising by single touch is to place the pole of the magnetising magnet in contact with the needle, drawing it repeatedly along the needle in the same direction. No method of magnetisation by single touch produces very strong magnetisation, and is very apt to produce consequent points. In what is known as "magnetism by divided touch," the opposite poles of two separate magnets of exactly equal strength are placed at the middle of the bar to be magnetised, and are then drawn simultaneously in opposite directions towards the ends of the bar. On reaching these Fig. 68a Fio. 50.--Magnetisation By Divided Touch ends, the magnets are returned through the air, again placed at the centre of the bar and the same mot...
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Add this copy of The Wonder Book Of Magnetism to cart. $20.57, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
Add this copy of The Wonder Book of Magnetism (Paperback Or Softback) to cart. $26.26, new condition, Sold by BargainBookStores rated 4.0 out of 5 stars, ships from Grand Rapids, MI, UNITED STATES, published 2022 by Legare Street Press.
Add this copy of The Wonder Book Of Magnetism to cart. $30.01, new condition, Sold by Ingram Customer Returns Center rated 5.0 out of 5 stars, ships from NV, USA, published 2022 by Legare Street Press.
