Answer:
19.642 cm
Explanation:
f₁ = Focal length of first lens = 11 cm
f₂ = Focal length of second lens = -25 cm
Combined focal length formula
Combined focal length is 19.642 cm
The correct answer would be <span>Magnesium oxide
Hope this helped :)
</span>
Particles in the liquid state of matter are close together, yet free to move around one another
The reflected beam of light passes through the focal point of the mirror.
In fact, a ray travelling parallel to the principal axis of a concave mirror passes through the focal point after it is reflected back from the mirror. This can be seen for instance in this figure:
http://www.cyberphysics.co.uk/graphics/diagrams/light/mirrors/concave_ray1.gif
where the situation described by the problem is shown with the red ray: the beam travels parallel to the principal axis and it is reflected through the focal point.