Всего 3 во тестовой формы, очень надо В каких средах с ростом температуры проводимость увеличивается?
а) в металлах
б) в вакууме
в) в полупроводниках
г) во всех

2. В находится примерно 18*10^23 молекул газа. Определите количество вещества.
а) 0,5 моль
б) 0,5 кмоль
в) 3 моль
г) 3 кмоль

3. С какой по величине силой взаимодействуют заряды 2 Кл и 1Кл, на расстоянии 2 м между их центрами?
а) k
б) 2k
в) k/2
г) 4K

Это если кратко
Рубиновый лазер преимущественно работает в импульсном режиме и генерирует излучение на длине волны =0,6943 мкм. Из-за возможностей получения больших импульсных мощностей, а также наличия рубиновых кристаллов высокого оптического качества рубиновый лазер и в настоящее время один из наиболее известных твердотельных лазеров.

Рубин – драгоценный материал, в чистом виде редко встречающийся в природе. Это диамагнитный кристалл окиси алюминия Al2O3 (-корунда) c парамагнитными примесными ионами хрома Cr3+. В зависимости от концентрации хрома кристалл -корунда принимает различные цвета: 0,5% Cr – ярко красная, более 8% Cr- зеленый цвет кристалла.

please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please please