PHYSICS
NAME ___________________________
LAB: RAY BOX
DATE ________________ PERIOD ____
IND E X O F RE FR A CTIO N O F W ATE R A ND K A R O
LAB PARTNERS: _____________, _____________
(a) On the separate sheet provided, place the flat side of the semicircular plastic dish (about 2/3
filled with liquid) E XAC TLY along the solid line, with the scratch mark at the middle of the dish
EXA CT LY at the center mark on the line. Be sure the dish itself is BELOW the line, in the region
marked LIQU ID .
(b) Aim a single light ray from the ray box so that it travels in a ir , hits the ce nte r mark on the
fl at side, and enters the l iq ui d with an angle of i nci de nc e of 20°.
(c) CA R EFU LLY mark one point on the re fr act e d ray. Since the center mark on the line is also on
this ray, you now have two points on the ray.
(d) Use a ST R AIGHT ED GE and a pe nci l to draw the refracted ray. Be sure to put A R RO WH EA D S
on the ray.
(e) Measure the angle of refraction, and record in the table below.
(f) Repeat steps (b)-(e) on the same drawing for angles of incidence of 30°, 40°, 50°, and 60°.
(f) Complete the table below by looking up the sin values for each trial and performing the division
indicated.
(g) Repeat entire procedure for other liquid.
θi
sin θi
WATER
θr
sin θr
20
30
40
50
60
///////// ///////// ///////// AVERAGE
sin
sin
θi
θr
KARO
θr
sin θr
sin
sin
θi
θr
///////// AVERAGE
Each lab partner should attach o ne "dish sheet" to his/her lab report and check the corresponding
box below. If there are three people in the group, the third person should check the third box.
There should not be more than three people in a group!
 water "dish sheet" attached
"dish sheets"
 Karo "dish sheet" attached
 see lab partners' reports for
QUE STIO NS /CO NC LU S IO N:
1. The experimental value (to 2 decimal places) for the index of refraction of water is ________.
2. The accepted value (to 2 decimal places) for the index of refraction of water is ________.
3. The experimental value (to 2 decimal places) for the index of refraction of Karo syrup is ______.
4. The accepted value (to 2 decimal places) for the index of refraction of air is ________.
5. When light travels from air into either water or Karo syrup, the light is bent
a way fr om > the normal.
< to wa rd >
6. Light is bent toward the normal when it travels from a material with a < hi gh>
< low >
index of refraction into a material with a < hi gh >
< low >
index of refraction.
<