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A-Level PhysicsYear 2021Q15

14 15 One of the largest stars in our galaxy is VY Canis Majoris. This star’s radius is 1420 times the radius of the Sun. The luminosity of this star is 270 000 times the luminosity of the Sun. A student states that the surface temperature of VY Canis Majoris must be much greater than the surface temperature of the Sun. (a) Determine whether the student’s statement is correct. surface temperature of Sun = 5780 K luminosity of Sun = 3.85 × 1026 W radius of Sun = 6.96 × 108 m (3) .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................. (b) Calculate the wavelength with maximum intensity in the black body radiation spectrum of VY Canis Majoris. (2) ................................................................................................................................................................................................................................................... ................................................................................................................................................................................................................................................... ................................................................................................................................................................................................................................................... Wavelength = .................................................................... Turn over 15 (c) Add the position of VY Canis Majoris to the Hertzsprung Russell diagram to determine which type of star it is. (2) 24 000 Luminosity / Lʘ 12 000 6000 3000 Temperature / K 106 104 102 1 10−2 10−4 Type of star .................................................................... (Total for Question 15 = 7 marks)

Paper Source:9PH0_02_que_20211015.pdf

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Exam Specification Info

This question is part of the UK A-Level Physics syllabus. In the actual exam, structured questions typically require linking specific keywords to gain full marks. Applaa helps you drill these topics.

Syllabus levelAdvanced Level (A-Level)

SubjectPhysics

Official MarksVariable (2–6 marks)