FRAMES OF REFERENCE
Ine rtial Frame o f Re fe re nc e
A frame of reference where Newtons Laws of Motion hold
A frame of reference that is at rest or moving with constant
velocity is an inertial frame of reference.
No n-ine rtial Frame o f
na sin a = ni sin i
(1) sin 90 = (1.309) sin i
i = 49.8o
ni sin i = nw sin w
(1.309) sin 49.8 = (1.333) sin w
w = 48.6o
ng sin g = nw sin w
ng sin 45 = (1.33) sin 90
ng = 1.88
1.66 sin 25 = (1.00)
s ' 16cm 12cm
s ' = 48cm
(b) s ' = 48cm Theimageislocated48cmbehindthemirrorandis
4m + s
s = 3.20 m s' = 7 . 20 m
f R 3.20m 7.20m
R = 4.43 m
f 16cm 12cm
f = 48cm diverging lens
(8.50mm) = +6.38mm
( see figure )
= (1.52 1)
s ' 17.95 24cm
s ' = 71.2cm
f = 17.95cm
Interference refers to a situation when two or more waves
Principle of Superposition when
two or more waves overlap, the
resultant displacement at any point
and any instant is found by adding
1. If a permanent bar magnet is free to rotate, one end would point
1. How does varying the locations of the light sources with respect to the photometer affect
the results of the experiment?
If the two light sources have the same intensity, their distances from the photometer are
the same. If we set the t
1. To familiarize students with basics of photometry.
2. To explore the phenomenon of inverse square law.
3. To explore the phenomenon of polarization.
In this experiment, we were able to familiarize the basics of photometry by explo
1. At 100% transmittance, are the distances of the two sources from the photometer equal?
Is this the expected result? Explain.
Yes, it must be equal if the light sources intensities are equally transmitted to the
photometer. However, in the actu
1. Monochromatic light is incident upon a slit of width 0.55mm. a diffraction patter is
formed on a screen 1.50m away. If the distance from the central maximum to the first
minimum is measured to be 1.25mm, what is the wavelength of the light?
1. How does slit width affect the results of the experiment? How about slit-screen
separation? Are the experiment results consistent with the theory?
The light is more diffracted if the size of the slit width is closer to the size of the
1. To explore the phenomenon of diffraction of light.
2. To compare single slit diffraction and two slit interference.
In this experiment, we were able to explore the phenomenon of diffraction of light.
1. In single-slit diffraction, how does the position of the 1 st dark fringe vary with the slit
When the slit width is increased, the position of the first dark fringe (above or below) is
closer to the line in line with the center of the w
Unlike incandescent light sources that emit
electromagnetic waves at different times and in
different directions, lasers produce an intense,
nearly parallel beam of coherent light.
Because the light waves are in phase in laser,
they interfere const
1. If the transparent material has an index of refraction of 1.60, what is the angle of
incidence beyond which total internal reflection occurs?
The total internal reflection occurs when a light ray strikes the material at an angle
1. To study the refraction of light.
2. To compare the angle of incidence in the first medium to the angle of refraction in the
3. To determine the index of refraction of glass experimentally by applying the Snells Law.
1. Why cant a material have an index of refraction less than 1.00?
Index of refraction is the measure of the speed of light in a particular medium. It is
expressed as the ratio of the speed of light in vacuum and the speed of light in a medium.
To determine the focal length of a convex lens using:
a. Different locations of the object
b. The graphical method
For this experiment, we were able to determine the focal length of a convex lens in
different ways. It is by using the
A periscope is an optical device which allows an observer to see
things which are beyond his or her line of sight. One of the classical uses of
a periscope is in submarines. Instead of needing to surface to see what is
going on at
1. In the experiment, is the image formed real or virtual? Justify your answer.
The image formed in the experiment is virtual because the lenses used were convex
lenses. It is also virtual because it has a positive image distance, meaning
1. In Table A, Why is the focal length of the lens equal to the image distance?
The focal length of the lens is equal to the image distance because the object distance is
very long and indefinite. The light ray from the tip of the object that cro
Determine the number of image formed when plane mirrors are placed at a certain angle.
To be able to determine and describe the image formed using a plane and spherical mirrors.
To determine and compute the focal length of spherical mirror.
APPLICATIONS OF MIRRORS
A mouth mirror or dentist's mirror is an instrument used in dentistry. The
head of the mirror is usually round, and the most common sizes used are the No. 4
and No. 5. A No. 2 is sometimes used when a smaller mirror is
1. In determining the number of images formed between two plane mirrors placed at
an angle, what happens when the angle is greater than 180? What are the limitations
of the angle then?
When the angle is greater than 180, there will be no
1. Can a convex mirror produce real images? If yes, describe how. If no, why not?
Yes, since the focus of a convex mirror is behind the mirror, it must be done in a different
orientation of the materials. We can do it if we include the situation
To study the nature of magnetic fields around the poles of magnets
To determine the magnitude of magnetic force on a current-carrying wire
To study the nature of the relationships between magnetic force and magnetic field, current,
length and o
Answers to Guide Questions
1. What happens to the distribution of magnetic flux lines when the iron ring was
placed between the U-magnets?
Attraction occurs on the unlike poles of the 2 U-magnets. When the iron ring is placed
between them, it is already i