The physics archive contains legacy physics content, and is not being updated with new content. For our most up-to-date, mastery-enabled courses, check out Middle School Physics, High School Physics, …

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Ups. Algo salió mal. Por favor inténtalo otra vez. Oh no, parece que encontramos un error. Necesitas actualiza. Si este problema persiste, avísanos.

Opa. Algo deu errado. Por favor, tente novamente. Ah não, parece que ocorreu um erro. Você precisa atualizar. Se o problema persistir, fale conosco.

In the physics sense, you are doing no work on the book. However, even if you don't have a book in your hand, if you twist side to side, your muscles get warm and you release energy.

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Ой! Что-то пошло не так. Пожалуйста, попробуйте повторить Ваши действия еще раз. Ой, мы кажется столкнулись с ошибкой. Вам нужно обновите страницу. Если эта проблема …

Unit 1: Forces and Newton's laws of motion About this unit For our most up-to-date, mastery-enabled courses, check out High School Physics, AP Physics 1, and AP Physics 2!

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