Final Exam—Physics Lab II—PHYS 104-1T
Spring 2011
125 pts
Name_______________________________
1) Practical Component (15 pts). Draw a ray, using the parallax method, through the provided glass slab.
Measure and label the incident and refracted angles. Calculate the index of refraction of glass (the index of
refraction for air is 1.0).
Incident angle=
____________
Refracted angle=
____________
Index of refraction= ____________
PHYS 104-1T Final Exam
3 May 2011
1
2) Practical component (20 pts) Station #:_______________
Set up a two lens system with the big lens closest to the object (ie. first) and the smaller lens after it;
calculate the focal lengths of both lens. Also, determine the total magnification of the system of lenses.
Draw a figure of the two lenses here, showing all pertinent distances and calculations; the figure should look
similar to that in Problem 6 with all object and image distances labeled.
fbig=_____________cm
fsmall=_____________cm
M=_______________
PHYS 104-1T Final Exam
3 May 2011
2
3)(15 pts) The following table gives the current measured when a power supply is connected to a series of
resistors. Plot the data, and graphically determine the voltage provided by the power supply.
V=__________ volts
R ( ohms)
1
2.4
3.2
5.4
8
11
I (amps)
2.8
1.3
0.9
0.5
0.4
0.3
4) (5 pts) Sketch the circuit for of a multiplier resistor used to increase the range of a voltmeter. Describe
how it increases the range of the voltmeter.
5) (4 pts) Describe how a galvanometer works.
PHYS 104-1T Final Exam
3 May 2011
3
6) (10 pts) What is the total magnification of the object, which is located 20 cm to the left of the first lens,
for this system of convex lenses. (This is not a compound microscope.)
7) (6 pts) Sketch two light rays originating from the object, whose position is labeled with an “X;” this
object is in front of a flat mirror, represented as the line in this figure. With these two rays, locate the
position of the image. Measure and label the image and object distances.
X
_________________________________________________________
PHYS 104-1T Final Exam
3 May 2011
4
8) (5 pts) How is a tangent galvanometer used to measure the Earth’s magnetic field. In your explanation,
sketch the vectors representing the Earth’s B-field and the B-field created by the tangent galvanometer.
9) (15 pts) Given in this table is the data for the number of turns of wire, current, and the angle of deflection
for a tangent galvanometer. The radius of the coil of wire is 0.4 m. Graph the data appropriately and
calculate the Earth’s magnetic field.
N
5
5
10
15
15
I (Amps)
Angle (deg)
0.33
28
0.9
52
0.5
51
0.3
48
0.5
60
PHYS 104-1T Final Exam
3 May 2011
5
10) (6 pts) Following is a schematic showing the 6 terminals on a double-pole, double-throw switch as it is
used in a circuit.
If the switch is in the “Down” position, show the path that the current takes through the circuit.
11) (4 pts) What is the purpose of a double-pole double-throw switch?
PHYS 104-1T Final Exam
3 May 2011
6
12) (5 pts) Sketch the path of the incident light ray through this glass prism:
13) (6 pts) Calculate the magnification of the compound microscope in this figure:
PHYS 104-1T Final Exam
3 May 2011
7
14) (4 pts) What causes chromatic aberration? Draw a figure and explain.
15) (3 pts) How are stars classified as different spectral types?
16) (2 pts) Is the following emission spectrum from a hydrogen or helium gas lamp?
PHYS 104-1T Final Exam
3 May 2011
8
Equations:
V  IR
NI 
2 RB E

tan
(where BE is the Earth’s magnetic field)
  4 10 7 Tm/A
h'
q

h
p
1 1 1
 
p q f
M 
M
 25 x'
fo fe
(Magnification of a compound microscope)
PHYS 104-1T Final Exam
3 May 2011
9