Explain what happens during a supernova, what features it produces, and the process of nucleosynthesis

Question 12 Nuclear fusion is a process which releases large amounts of energy and takes place in the core of stars like our Sun. Explain what is meant by nuclear fusion and the conditions necessary for it to take place. [about 150 words TUTARIA xecfureter pitztenen fargeping tontien SEAGA tallerkitty KAMIRIKIA Tantaastattes Forterrebenta Tank-Taric Hartafferies Whyteuffer ENDRERITAT ESFISSTEHALE SUSECTIONE STMENTEEL itaftarly RICERCAGE evements teleidens RISTISTATASTE athleschicht JEZERSITE GAMBAR 4315742424 Satelit Stimale Ras MUJERESES Sosyesyevelse 284 SHITA BRAWLIBETTEREM Intermit GIGIRIGEN EN ANDJESTHE LAE THUIZEMIE BURE POTESISIHAE JITHASEL

A main sequence star of mass 25 M⊙has a luminosity of approximately 80,000 L⊙. a. At what rate DOES MASS VANISH as H is fused to He in the star’s core? Note: When we say “mass vanish '' what we really mean is “gets converted into energy and leaves the star as light”. Note: approximate answer: 3.55 E14 kg/s b. At what rate is H converted into He? To do this you need to take into account that for every kg of hydrogen burned, only 0.7% gets converted into energy while the rest turns into helium. Approximate answer = 5E16 kg/s c. Assuming that only the 10% of the star’s mass in the central regions will get hot enough for fusion, calculate the main sequence lifetime of the star. Put your answer in years, and compare it to the lifetime of the Sun. It should be much, much shorter. Approximate answer: 30 million years.

How much energy would be released if a star with a mass of 25 Msun and a radius of 10 Rsun detonates as a supernova explosion in 1 second? (Hint: think about the definition of binding energy). Express your answer in terms of solar luminosities.