Answer:
A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible. The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.
Answer:
The cornea of an eye is avascular
Explanation:
The healing process in case of a cornea transplant is slow, because the cornea is of an eye is avascular, i.e., it does not contain blood vessels and in the absence of the blood vessels in the cornea tissue the nutrients and oxygen is not able to get delivered there.
Thus the immune system, without the blood vessels in the cornea is weak and hence healing takes time in case of cornea transplant.
Answer: Black hole.
Explanation:
As the massive star "compacts" under its own gravity, it triggers a massive supernova, after this point the remains of the star can become a neutron star, which is a very compact star made primarily, as the name says, of neutrons. The other possibility is a black hole, which is a finite region of space wherein it's interior there is a big concentration of mass, which creates a gravitational field strong enough that there is no particle that can escape it.
Answer:
0.85 c
Explanation:
When the two travel at right angles to each other , their relative velocity is given by the hypotenuse formed by the x and y direction velocities.
Relative velocity of the two protons is given as
If v = 3/5 c , then the relative speed = 
(3/5c) =0.85 c
Answer:
Fluorescent lighting is usually used.
Explanation:
