Physics, 26.09.2019 05:30 Angelanova69134

Why do concave lenses always form virtual images?

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A concave mirror and a converging lens will only produce a real image if the object is located beyond the focal point (i.e., more than one focal length away). The image of an object is found to be upright and reduced in size.

Answer from: kaytlynnmeyer

Explanation:

There are two types of images formed by the lenses or mirrors.

1. Real image: When two refracted or reflected rays actually meet at a point after refraction or reflection, the image formed is real.

2. Virtual image: When two refracted or reflected rays appear to meet at a point after refraction or reflection, the image formed is virtual.

A concave lens is a diverging lens, it means when the rays of light incident on the concave lens, then after refraction, the rays diverges from its original path. Thus, they cannot meet at a point, they appears to comes from a point and the image formed is virtual.

Answer from: Quest

sleep paralysis is a parasomnia, events associated with sleep.

sleep paralysis happens when you are in the middle of waking up or falling asleep. it is the feeling of being conscious but unable to move. it definitely involves hallucinations.

i had a friend that had sleep paralysis and he told me a story one time where he was laying in bed and he couldn't move his body no matter how hard he tried and there was someone standing in the corner of his room coming towards him. he couldn't move and you can't "wake up" because you are already conscious. sometimes sleep paralysis can be triggered by frequent waking up during the night based off of multiple trips to the bathroom, or if you had ever been abused, sleep paralysis can start happening from things like that.

Answer from: Quest

multiply 2kg by latent heat of vap

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