{"id":270,"date":"2015-12-27T19:24:10","date_gmt":"2015-12-27T18:24:10","guid":{"rendered":"http:\/\/www.igatamus.com\/bgc\/?p=270"},"modified":"2017-10-06T19:24:40","modified_gmt":"2017-10-06T17:24:40","slug":"geometrie-ombre-portee-angles-azimut-elevation","status":"publish","type":"post","link":"https:\/\/www.igatamus.com\/bgc\/2015\/12\/27\/geometrie-ombre-portee-angles-azimut-elevation\/","title":{"rendered":"G\u00e9om\u00e9trie ombre port\u00e9e, angles azimut \u00e9l\u00e9vation"},"content":{"rendered":"

Rappels :<\/p>\n

L’Azimut d’un point observ\u00e9 est l’angle entre le nord (magn\u00e9tique ou g\u00e9ographique) et le point observ\u00e9 selon un plan horizontal. Exemple si je regarde \u00e0 l’EST l’azimut est 90\u00b0<\/p>\n

L’\u00e9l\u00e9vation est l’angle enter l’horizon et un un point observ\u00e9 dans le ciel, il est compt\u00e9 positivement si on monte et n\u00e9gativement si on descend<\/p>\n

Triangle rectangle :<\/p>\n

sin(Angle)= c\u00f4t\u00e9 oppos\u00e9 \/ Hypot\u00e9nuse<\/p>\n

cos(Angle) = c\u00f4t\u00e9 adjacent \/ Hypot\u00e9nuse<\/p>\n

Tan(Angle) = c\u00f4t\u00e9 oppos\u00e9 \/ c\u00f4t\u00e9 adjacent<\/p>\n

Exemple de mesure d’\u00e9l\u00e9vation, si on mesure l’ombre port\u00e9e d’un objet, en l’occurence mon four solaire hauteur du four = 58 cm, ombre = 95 cm le 6 f\u00e9vrier 2013<\/p>\n

|<\/p>\n

|<\/p>\n

58 cm |<\/p>\n

|_________<\/p>\n

95 cm<\/p>\n

hypot\u00e9nuse = rac(58\u00b2+95\u00b2)= 111.13<\/p>\n

ArcCos (95\/11.13) = 31.40 \u00b0<\/p>\n

Si on regarde sur un site comme :<\/p>\n

http:\/\/www.sunearthtools.com\/dp\/tools\/p … hp?lang=fr<\/a><\/p>\n

et que l’on demande \u00e0 Vidauban l’\u00e9l\u00e9vation \u00e0 12h00 GMT le f\u00e9vrier 2013 on nous donne : 31.37 \u00b0<\/p>\n

Donc mesure confirm\u00e9e<\/p>\n","protected":false},"excerpt":{"rendered":"

Rappels : L’Azimut d’un point observ\u00e9 est l’angle entre le nord (magn\u00e9tique ou g\u00e9ographique) et le point observ\u00e9 selon un plan horizontal. Exemple si je regarde \u00e0 l’EST l’azimut est 90\u00b0 L’\u00e9l\u00e9vation est l’angle enter l’horizon et un un point observ\u00e9 dans le ciel, il est compt\u00e9 positivement si on monte et n\u00e9gativement si on … <\/p>\n

Continuer la lecture de « G\u00e9om\u00e9trie ombre port\u00e9e, angles azimut \u00e9l\u00e9vation »<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[16],"tags":[],"_links":{"self":[{"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/posts\/270"}],"collection":[{"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/comments?post=270"}],"version-history":[{"count":1,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/posts\/270\/revisions"}],"predecessor-version":[{"id":271,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/posts\/270\/revisions\/271"}],"wp:attachment":[{"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/media?parent=270"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/categories?post=270"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.igatamus.com\/bgc\/wp-json\/wp\/v2\/tags?post=270"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}