2021年08月03日

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20.07589080936JSite->dispatch( ).../index.php:42
30.07629098536JComponentHelper::renderComponent( ).../application.php:194
40.07809142520JComponentHelper::executeComponent( ).../helper.php:348
50.07809163320require_once( '/home/users/1/jein/web/jein/components/com_content/content.php' ).../helper.php:380
60.07999436816JController->execute( ).../content.php:16
70.07999437200ContentController->display( ).../controller.php:761
80.08309987088JController->display( ).../controller.php:74
90.086310559864ContentViewArticle->display( ).../controller.php:722
100.101611790344JDispatcher->trigger( ).../view.html.php:121
110.101611792152JEvent->update( ).../dispatcher.php:161
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130.101611793152plgContentJw_allvideos->onContentPrepare( ).../event.php:71
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20.07589080936JSite->dispatch( ).../index.php:42
30.07629098536JComponentHelper::renderComponent( ).../application.php:194
40.07809142520JComponentHelper::executeComponent( ).../helper.php:348
50.07809163320require_once( '/home/users/1/jein/web/jein/components/com_content/content.php' ).../helper.php:380
60.07999436816JController->execute( ).../content.php:16
70.07999437200ContentController->display( ).../controller.php:761
80.08309987088JController->display( ).../controller.php:74
90.086310559864ContentViewArticle->display( ).../controller.php:722
100.101611790344JDispatcher->trigger( ).../view.html.php:121
110.101611792152JEvent->update( ).../dispatcher.php:161
120.101611793072call_user_func_array:{/home/users/1/jein/web/jein/libraries/joomla/event/event.php:71} ( ).../event.php:71
130.101611793152plgContentJw_allvideos->onContentPrepare( ).../event.php:71
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棒磁石の周りの磁界(EM-M-04)

<棒磁石の周りの磁界>

 

棒磁石の周りでは、鉄をひきつける力が働きます。
クリップを使って棒磁石のどこにどんな力が働いているか、調べてみましょう。クリップが何個連なってくっつくかで磁力の強さも分かりますね。方位磁針を置いてみると、その力の向きもよく分かりますね。調べてみましょう。
こういう力が働く環境が周りにできるので、これを磁界(あるいは磁場)といいます。不思議ですね。