Harry is reading an online summary of the law of reflection. the site states that after light hits a mirror, the angle of reflection is the angle between the reflected ray and the normal, which is the surface of the mirror.
which statement corrects an error on the site?
the normal is a line perpendicular to the surface of the mirror.
the normal is a line perpendicular to the incoming ray.
the angle of reflection is the angle between the incoming ray and the normal.
the angle of reflection is the angle between the reflected ray and the incoming ray.

The normal is a line perpendicular to the surface of the mirror.

Explanation:

By definition, the normal to a surface corresponds to a line perpendicular to the surface. Therefore, the normal of a mirror is perpendicular to the surface of the mirror. So, the statement

"the normal, which is the surface of the mirror."

is wrong.

The law of reflection states that the angle of incidence on the surface of a mirror is equal to the angle of reflection, where the two angles are defined as:

- Angle of incidence: the angle between the incoming ray and the normal to the mirror

- Angle of reflection: the angle between the reflected ray and the normal to the mirror

its c i just checked it

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.