8. Light and Lenses EQUATIONS

Question 1

8 (Equation) What is the equation for magnification?

Answer 1

m= magnification (unitless)
i= distance between image and the mirror
o= distance between the object and the mirror

note the negative sign

When the image is less than than the object distance, the object is minimized. When the image distance is greater than the object distance, the object is magnified.

magnification
| m |>1 indicates magnification

magnification
| m |<1 indicates minimization

m |> 1 indicates

Question 2

8 (Equation) What is the equation for the index of refraction of a medium

Answer 2

n= dimensionless quality called the index of refraction of the medium
c= speed of light in a vacuum
v= speed of light in a medium
FYI: to give context, the index of refraction of air is 1

Question 3

8 (Equation) What is the equation to determine the angle of light rays when they pass from one medium to another?

Answer 3

n1 sinӨ1= medium from which the light is coming
n2 sinӨ2=Medium into which the light is entering

n= you get this value from equation of speed in a medium (n=c/v)

You measure the angles in relation to the ‘critical angle’ down the middle

Question 4

8 (Equation) What equation do you use for magnification and distance between objects for lenses?

Answer 4

It’s the same for mirrors.

o= distance between the object and the mirror
i= distance between the image and the mirror
r= radius of the curvature
f= focal point

m= magnification (unitless)
i= distance between image and the mirror
o= distance between the object and the mirror

Question 5

8 (Equation) What is the equation for the power of a lens?

Answer 5

P=power of lens
f= focal length

Question 6

8 (Equation) what is the equation for focal length when you add multiple lenses together?

Answer 6