p106. q14. ch31 .Faraday's Law

1 A rectangular coil of wire has dimensions 0.24m by 0.18m. A 25T magnetic field passes

through the coil at an angle of 15 degrees from perpendicular. What is the magnetic flux

through the coil?

A 0.28 Wb

B 0.44 Wb

C 0.60 Wb

D 1.04 Wb

E 1.80 Wb

2 A square coil of wire has dimensions of 1 x 1 m in the plane of this screen. A 1T magnetic

field passes through the coil into the screen at an angle of 0 degrees from perpendicular. If

the magnetic flux decreases by 1 Wb/s, what is the voltage one would measure across a

small gap in the wire loop?

A 1 V

B 2 V

C 3 V

D 4 V

E 5 V

3 Again take a square coil of wire having dimensions of 1 x 1 m in the plane of this page. A

1T magnetic field passes through the coil into the screen at an angle of 0 degrees from

perpendicular. If the magnetic flux decreases by 1 Wb/s and the loop is now a complete

circuit, the resulting current in the loop will create an magnetic field

A into the screen

B out of the screen

C to the left

D to the right

E No current will result in the loop

4 Two parallel rods extend from a resistor of 2 Ohms. A uniform 0.8 T magnetic field makes

an angle of 60 degrees with the normal to the page. A 60 cm conducting bar 90 deg. to

the rods connects them and slides away from the resistor at 10 m/s. What is the current in

the resistor?

A 2.1 A

B 1.6 A

C 1.2 A

D 2.4 A

E 1.0 A

p106. q15. ch32. EM Induction

1 A long solenoid has 5000 turns per meter and carries a current of 20A. What is the energy

density inside the solenoid? Answer in Joules/m3.

A 1327

B 6283

C 50000

D 148

E 2.5

2 A small battery is connected in a loop circuit in series with a 1 kilo Ohm resistor and

inductor.. A switch in the circuit delivering the battery voltage which was closed is opened.

Another switch in a wire bypassing the battery and its switch is simultaneously closed so

the circuit ``discharges”. What is the inductance if the current decreases to 1/3 of its

initial value 30 micro seconds after the discharge switch is closed?

A 74 mH

B 99 mH

C 49 mH

D 62 mH

E none of the above

3 A fixed inductance of L=2.10 micro H is used in series with a variable capacitor in the

tuning circuit of a radio. What capacitance tunes the circuit for a station which broadcasts

at 6.30 MHz?

A 76 pF

B 152 pF

C 304 pF

D 608 pF

4 A small battery is connected in a loop circuit in series with a 1 kilo Ohm resistor and

inductor. A switch in the circuit is open. What is the inductance of this circuit if the current

INCREASES to 1/3 of its FINAL value in 30 micro seconds after the switch is closed?

A 74 mH

B 99 mH

C 49 mH

D 62 mH

E none of the above

p106. q16. ch33. AC Circuits

1 A transformer connected to a 30,000 rms V ac generator is to supply 345,000 V to a

transmission line. There are 80 turns in the primary coil of the transformer. The number of

turns in the secondary must be

A 6

B 70

C 920

D 9200

E 12

2 What is the net impedance in an RLC series circuit if the imposed voltage has a frequency

of =500,

R=1000 Ohms, C=1 micro F, and L=1 H?

A 600 Ohms

B 1200 Ohms

C 1800 Ohms

D 2300 Ohms

E 1100 Ohms

3 3. If a series RLC circuit has an impedance of 1000 Ohms and an imposed rms voltage of

141.4 V, what is the rms current in the circuit?

A 0.141 A

B 0.282 A

C 0.564 A

D 1.128 A

4 4. What relative values must X_L and X_C have to obtain the maximum rms I in an RLC

series circuit?

A X_L = 0.5 X_C

B X_L = X_C

C X_L = 2 X_C

D X_L = 10 X_C

5 An LC circuit is to have resonant oscillations at 5 Hz. Find the value of a capacitor which

will work with a 1.0 mH inductor.

A 2 F

B 1 F

C 0 F

D 0.1 F

p106. q17. ch34. Electromagnetic Waves

1 Light intensity is measured in units of ______

A W/m^2

B Wm^2

C m^2/W

D W^2/m

2 A light wave between the gamma and x ray types has a frequency of 10^(19) Hz. What is

its wavelength?

A 3 x 10 ^(-12) m

B 3 x 10 ^(-11) m

C 3 x 10 ^(-10) m

D 3 x 10 ^(-9) m

3 Light frequency (f) is mesured in units of ________, wavelength in ______, and they are

related to one another by ___________

A Hz; m; f=c/wavelength

B m; Hz; f=c/wavelength

C Hz; m; f=wavelength/c

D Hz; m; f=c x wavelength

4 Which of the lists below is in order of increasing wavelength, left to right

A gamma rays; x-rays; visual; infra-red

B infra-red; visual; x-rays; gamma rays;

C x-rays; gamma rays; visual; infra-red

D visual; x-rays; gamma rays; infra-red

5 Light intensity in terms of B alone is proportional to B^x where B is the amplitude of the

magnetic field oscillation of the wave. x=

A 4

B 3

C 2

D 1

p106. q18. ch35. Light & Geoptics

1 A real object is placed 10 cm from a converging lens that has a focal length of 6cm. Which

statement is most accurate?

A The image is real, erect, and enlarged.

B The image is real, inverted, and enlarged.

C The image is real, erect, and reduced.

D The image is real, inverted, and reduced.

2 What is the focal length of a lens that forms a virtual image 30cm from the lens when a

real object is placed 15cm from the lens?

A 10 cm

B 15 cm

C 30 cm

D 45 cm

3 What is the magnification of a lens that forms an image 20 cm to its right when a real

object is placed 10 cm to its left?

A 0.50

B 1.0

C 1.5

D -2.0

4 The index of refraction for water is 1.33 and that for glass is 1.50. A light ray strikes the

water/glass boundary with an incident angle of 30.00 from normal on the water side. Which

statement is most likely true for its refracted angle from normal in the glass?

A The angle of refraction is 26.30.

B The angle of refraction is 34.70.

C The angle of refraction is 30.00.

D The angle of refraction is 60.00.

5 When you get up in the morning and look at yourself in the bathroom mirror, you are

looking at a __________

A real image, behind the mirror

B virtual image, in front of the mirror

C real image, in front of the mirror

D virtual image, behind the mirror

p106. q19. ch36. Geo Optics & Opti Instruments

1 A magnifying lens has a focal length of 1cm. A person has a near point of 25cm. What is

the magnification of the lens for that person focussed at the near point?

A 1.6

B 2.6

C 26

D 56