Answer: The focal length of the cornea-lens system in his eye must be LESS THAN the distance between the front and back of his eye.
Explanation:
The human eye the front part of the eye is the CORNEA. This is the tough white transparent part of the eye that helps in the refraction of light rays. While the backside of the eye is the RETINA. This is the part of the eye when images are focused.
When a normal eye is at rest, parallel rays from a distant object are focused on the retina. The ability of the eye - lens to focus points at different distances on the retina is known as accomodation. The adjustment of the eye lens to focus objects of varying distances is brought about by the ciliary muscles. The have the ability to change the shape of the eye which leads to change in focal length.
When a person with normal vision looks at a distant object at infinity, the lens brings parallel rays to focus on the retina. Thus, the furthest point which the eye can see distinctly is called the far point of the eye and it's infinity for a normal eye. But Joe was able to focus his eye on the tree, meaning that the tree was within his near point. This is the nearest point at which an object is clearly seen. Therefore, when the effective focal length of the cornea-lens system changes, it changes the location of the image of any object in one's field of view.
Answer: The person sitting in the middle of the train sees the back of the train enter ing the tunnel before the front end comes out.
Explanation:
I'm not sure I completely understand the expression you want evaluated.
It looks like a fraction with the same exact thing in both the numerator and the denominator. A fraction like that always boils down to ' 1 '.
What causes it to form: <span>Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain. Human activities, power plants, and exhaust from vehicles all are causes.</span>
Affects on living things-
Acid rain can kill trees
It can affect plant growth patterns
Toxins can kill animals
Nonliving things-
It can decay building materials and paints
it breaks down rocks
Hope this helped! Mark brainliest?
Answer:
B. The atom gains 1 electron, to make a total of 18 electrons.
Explanation:
Chlorine is the 17th element in the periodic table, so it has atomic number 17:
Z = 17
This means that a neutral atom of chlorine has 17 protons and 17 electrons.
When a chlorine atom gains 1 electron, its electric charge (initially zero) becomes -1, since the electron has negative charge of -1 (in elemntary charge units). This also means that the number of electrons in the ion is now
17 + 1 = 18
So the correct answer is
B. The atom gains 1 electron, to make a total of 18 electrons
