Warning: fopen(/var/www/storage/cache/cache.catalog.language.1766691146): failed to open stream: No space left on device in /var/www/opencart/system/library/cache/file.php on line 49Warning: flock() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 51Warning: fwrite() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 53Warning: fflush() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 55Warning: flock() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 57Warning: fclose() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 59Warning: fopen(/var/www/storage/cache/cache.catalog.language.1766691146): failed to open stream: No space left on device in /var/www/opencart/system/library/cache/file.php on line 49Warning: flock() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 51Warning: fwrite() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 53Warning: fflush() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 55Warning: flock() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 57Warning: fclose() expects parameter 1 to be resource, bool given in /var/www/opencart/system/library/cache/file.php on line 59Задача 30485.
Определите объемную плотность энергии магнитного поля соленоида, если по обмотке течет ток 20 А, количество витков на единицу длины n=15 вит/см. Сердечник соленоида сделан из немагнитного материала.