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Monochromatic light of wavelength 490 nm falls normally on a diffraction grating that has 6 × 105
1
lines per metre. Which one of the following is correct?
A The first order is observed at angle of diffraction of 17°.
B The second order is observed at angle of diffraction of 34°.
C The third and higher orders are not produced.
D A grating with more lines per metre could produce more orders.
(Total 1 mark)
Light of wavelength λ is incident normally on a diffraction grating for which adjacent lines are a
2
distance 3λ apart. What is the angle between the second order maximum and the straight-
through position?
A 9.6°
B 20°
C 42°
D There is no second order maximum.
(Total 1 mark)
A narrow beam of monochromatic light falls on a diffraction grating at normal incidence. The
3 second order diffracted beam makes an angle of 45° with the grating. What is the highest order
visible with this grating at this wavelength?
A 2
B 3
C 4
D 5
(Total 1 mark)
Light of wavelength λ is incident normally on a diffraction grating of slit separation 4λ. What is the
4
angle between the second order maximum and third order maximum?
A 14.5°
B 18.6°
C 48.6°
D 71.4°
(Total 1 mark)
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Page 2 of 38
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A diffraction grating has 300 lines per mm. It is illuminated with monochromatic light of
5 wavelength 540 nm.
Calculate the angle of the 2nd order maximum, giving your answer to the appropriate number of
significant figures.
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
angle .......................................... degrees
(Total 4 marks)
A diffraction grating has 940 lines per mm.
6
(a) Calculate the distance between adjacent lines on the grating.
distance between lines .............................................
(1)
(b) Monochromatic light is incident on the grating and a second-order spectral line is formed at
an angle of 55° from the normal to the grating. Calculate the wavelength of the light.
wavelength .....................................
(3)
(Total 4 marks)
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Page 3 of 38
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A narrow beam of monochromatic light of wavelength 590 nm is directed normally at a diffraction
7 grating, as shown in the diagram below.
(a) The grating spacing of the diffraction grating is 1.67 × 10–6 m.
(i) Calculate the angle of diffraction of the second order diffracted beam.
answer .................................... degrees
(4)
(ii) Show that no beams higher than the second order can be observed at this
wavelength.
(3)
(b) The light source is replaced by a monochromatic light source of unknown wavelength.
A narrow beam of light from this light source is directed normally at the grating.
Measurement of the angle of diffraction of the second order beam gives a value of 42.1°.
Calculate the wavelength of this light source.
answer ....................................... m
(2)
(Total 9 marks)
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Page 4 of 38
Monochromatic light of wavelength 490 nm falls normally on a diffraction grating that has 6 × 105
1
lines per metre. Which one of the following is correct?
A The first order is observed at angle of diffraction of 17°.
B The second order is observed at angle of diffraction of 34°.
C The third and higher orders are not produced.
D A grating with more lines per metre could produce more orders.
(Total 1 mark)
Light of wavelength λ is incident normally on a diffraction grating for which adjacent lines are a
2
distance 3λ apart. What is the angle between the second order maximum and the straight-
through position?
A 9.6°
B 20°
C 42°
D There is no second order maximum.
(Total 1 mark)
A narrow beam of monochromatic light falls on a diffraction grating at normal incidence. The
3 second order diffracted beam makes an angle of 45° with the grating. What is the highest order
visible with this grating at this wavelength?
A 2
B 3
C 4
D 5
(Total 1 mark)
Light of wavelength λ is incident normally on a diffraction grating of slit separation 4λ. What is the
4
angle between the second order maximum and third order maximum?
A 14.5°
B 18.6°
C 48.6°
D 71.4°
(Total 1 mark)
@TOPhysicsTutor facebook.com/TheOnlinePhysicsTutor
Page 2 of 38
, theonlinephysicstutor.com
A diffraction grating has 300 lines per mm. It is illuminated with monochromatic light of
5 wavelength 540 nm.
Calculate the angle of the 2nd order maximum, giving your answer to the appropriate number of
significant figures.
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
...............................................................................................................................
angle .......................................... degrees
(Total 4 marks)
A diffraction grating has 940 lines per mm.
6
(a) Calculate the distance between adjacent lines on the grating.
distance between lines .............................................
(1)
(b) Monochromatic light is incident on the grating and a second-order spectral line is formed at
an angle of 55° from the normal to the grating. Calculate the wavelength of the light.
wavelength .....................................
(3)
(Total 4 marks)
@TOPhysicsTutor facebook.com/TheOnlinePhysicsTutor
Page 3 of 38
, theonlinephysicstutor.com
A narrow beam of monochromatic light of wavelength 590 nm is directed normally at a diffraction
7 grating, as shown in the diagram below.
(a) The grating spacing of the diffraction grating is 1.67 × 10–6 m.
(i) Calculate the angle of diffraction of the second order diffracted beam.
answer .................................... degrees
(4)
(ii) Show that no beams higher than the second order can be observed at this
wavelength.
(3)
(b) The light source is replaced by a monochromatic light source of unknown wavelength.
A narrow beam of light from this light source is directed normally at the grating.
Measurement of the angle of diffraction of the second order beam gives a value of 42.1°.
Calculate the wavelength of this light source.
answer ....................................... m
(2)
(Total 9 marks)
@TOPhysicsTutor facebook.com/TheOnlinePhysicsTutor
Page 4 of 38
