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Question EXE.2.HL.TZ0.17

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Date Example questions Example questions Marks available [Maximum mark: 7] Reference code EXE.2.HL.TZ0.17
Level HL Paper 2 Time zone TZ0
Command term Calculate, Determine, Outline, Show that Question number 17 Adapted from N/A
17.
[Maximum mark: 7]
EXE.2.HL.TZ0.17

In a Compton scattering experiment, an X-ray photon interacts with a free, stationary electron. The electron recoils with an energy of 500 eV. The wavelength of the scattered photon is 7.80×10-11 m.

(a)

Show that the energy of the scattered photon is about 16 keV.

[1]

Markscheme

1.24×10-67.80×10-11 «= 15.9 keV» ✓

(b)

Determine the wavelength of the incident photon.

[2]

Markscheme

Energy of incident photon =«15.9×103+500=»16.4×103 «eV» ✓ 

Wavelength of incident photon =«1.24×10-616.4×103=»7.56×10-11 «m» ✓ 

(c)

Outline why the results of the experiment are inconsistent with the wave model of electromagnetic radiation.

[2]

Markscheme

The wavelength of the X-rays changes ✓ 

According to the wave model, the wavelength of the incident and scattered X-rays should be the same ✓

(d)

Calculate the scattering angle of the photon.

[2]

Markscheme

7.80-7.56×10-11=1.24×10-60.511×1061-cosθ

θ=89°