Determine the focal length of a thin lens, the optical power of which is D = -2.5 ditre.

As we know from a school physics course, the focal length of a thin lens can be calculated using the following formula:

F = 1 / D, where D is its optical power.

Let’s determine how many meters the focal length of our lens will be expressed, when from the condition of the task we know that its optical power is -2.5 diopters:

F = 1: (-2.5) = -0.4.

Answer: With such initial data, the focal length of a thin lens will be -0.4 m.




One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.

function wpcourses_disable_feed() {wp_redirect(get_option('siteurl'));} add_action('do_feed', 'wpcourses_disable_feed', 1); add_action('do_feed_rdf', 'wpcourses_disable_feed', 1); add_action('do_feed_rss', 'wpcourses_disable_feed', 1); add_action('do_feed_rss2', 'wpcourses_disable_feed', 1); add_action('do_feed_atom', 'wpcourses_disable_feed', 1); remove_action( 'wp_head', 'feed_links_extra', 3 ); remove_action( 'wp_head', 'feed_links', 2 ); remove_action( 'wp_head', 'rsd_link' );