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Introducing new students to careers in physics
Owen Long Department of Physics and Astronomy, UC Riverside
UCR Physics Majors
• Currently 149 undergraduates – 68 new freshmen this year!
• Some demographics (recent graduates) – 25% underrepresented minority groups – 20% female – 48% first genera-on college students
Adam Green, 2nd year student
Adventures in Physics (Phys39)
• Required 3-‐unit class for new physics majors. – Learn what you can do with a degree in physics. – OpportuniSes for research and support.
• Components of the course – Career informaSon and exercises – PresentaSons from UCR Physics alumni – Faculty research presentaSons – Physics and Technology for Future presidents.
Misconcep-ons
• Only thing you can do with a BS degree in physics is go to grad school in physics.
• Only thing you can do with a PhD in physics is become a physics professor.
Misconcep-ons
• Only thing you can do with a BS degree in physics is go to grad school in physics.
• Only thing you can do with a PhD in physics is become a physics professor.
• This was my experience, but not typical. – I had to educate myself on what most of our students do aYer graduaSon.
UCR Physics Bachelor's Alumni
• Search of 281 Alumni from the past 25 years. • Found over 140 of them (50%) • They are all listed on this web page – h[p://www.physics.ucr.edu/undergrad/alumni-‐ugrad.html – Current occupaSon – Highest graduate degree earned – Link to their web page
• Can also find the page this way – UCR Physics > Undergraduate Program > Alumni
UCR Physics Bachelor's Alumni
• Graduate school / degrees (88/140, 62%) – Currently in grad school: 32
• MIT, CalTech, Stanford, UCSB, Ohio State, UCR, … • >14 Physics, 2 CS, 1 Chemistry, 1 Bioengineering, 1 Medical Physics, …
– Masters degree: 26 • Cal State LA, UCI, USC, UCR, CSULB, Cal State Fullerton, UCSC, … • 14 Physics, 9 Engineering, 2 applied physics
– Ph.D. : 30 • UCSC, Yale, U of Mass, UCR, UCLA, Stony Brook, Brigham Young, … • 17 Physics, 5 engineering, 2 chemistry, 1 medicine
h[p://www.physics.ucr.edu/undergrad/alumni-‐ugrad.html
UCR Physics Bachelor's Alumni • Health professions : 15 including 5 medical doctors. • Aerospace industry : 14 • InformaSon technology, data science, programming : 11 • Applied physics, including materials science : 9 • Teaching, high school : 9 • Teaching, college and university : 8 • ScienSst at a naSonal lab : 3
h[p://www.physics.ucr.edu/undergrad/alumni-‐ugrad.html
UCR Physics Alumni: • At least four UCR Physics alumni are
currently working at Loma Linda Medical Center (10 miles away in Redlands). – Medical Physicist, accelerator operators.
• Loma Linda has the first hospital-‐based proton accelerator in the US (built at Fermilab, opened in 1990).
• Robert Simpson and Alexis Quintal will be invited speakers this quarter – Alexis is an accelerator operator – Robert is a medical physicist (Georgia
InsStute of Technology, MSMP, Medical physics)
Protons lose most of their energy, ionizing atoms, just before stopping. Stopping distance can be finely tuned with the beam energy.
UCR Physics Alumni PresentaSons
• Medical Physics – proton therapy at Loma Linda
• Teaching – high school • Aerospace – literally a rocket scienSst • Data science – silicon valley tech companies • Research – JPL • Video game industry – Blizzard Entertainment
Advice from UCR Alumni • Learn what you enjoy through experience. • Research and/or Internship is very important. • Build a toolbox – skills are needed (problem solving, programming, esSmaSon, leadership, …)
– know how to "do stuff" • Networking is valuable • Have a goal but be flexible
Excellent advice and guidance on how to prepare for and execute a job search.
hFps://www.spsna-onal.org/careerstoolbox
American InsStute of Physics StaSsScs
• Excellent resource for understanding career opSons and career development.
• Google "aip" or just go to www.aip.org.
• I will summarize some of the StaSsScal Research from the AIP site. Go there for the complete reports.
Physics Bachelor's degree, One year aYer graduaSon
• More than half go on to graduate school (MS or PhD program).
• Some who iniSally seek employment aYer their Bachelor's degree intend to go to grad school later.
• Some begin very saSsfying long-‐term careers with their Bachelor's degree.
Graduate School, Fields of Study
• ConSnuing in physics is most common, but many change fields.
• Your Bachelor's degree in physics is an excellent preparaSon for many fields.
Financial Support in Graduate School
Grad School is FREE!!!*
If you are admi[ed to a grad program, they think you will succeed and will support you through it. Admission at presSgious insStuSons is very compeSSve. You don't pay tuiSon. The school pays you! Enough to pay your living expenses so you don't need a day job, though you won't get rich on a grad student sSpend.
*Except Med school and Law school
Aside on Law and Medicine Average Med school entrance
exam score by major Average Law school entrance
exam by major
Physics majors do very well on these entrance exams. Ironically, the worst majors (on average) are Premed and Criminal JusSce!
Average of Physics is at 85th percen-le Average of Physics is at 87th percen-le
Physics and Technology for Future Presidents
• Textbook for the course.
• Shows the deep relevance of physics in important issues that affect society – nuclear energy, nuclear bombs, opScs,
fluids, ba[eries, lasers, x-‐rays and gamma rays, MRI, CAT, and PET scans, …
• Hope to engage and inspire the students
Topics covered
• Energy • Nuclei, RadioacSvity, Chain ReacSons, Bombs • Gravity, Rockets, Air Resistance • Light • Invisible Light • Climate Change • Quantum Physics
TNT vs Chocolate Chip Cookies
Which has more stored chemical energy per gram?
Cookies have 8 Smes higher energy density (energy / gram) compared to dynamite!
TNT vs Chocolate Chip Cookies Cookies have 8 Smes higher energy density (energy / gram) compared to dynamite!
The big difference is the power (energy / Sme). Energy in dynamite is released very quickly (explosive). Feed this guy enough cookies, and he can also do it, but it will take a lot longer.
Solar Powered California PopulaSon is about 40 Million. Typical house uses about 1 kW of power. Peak power demand for state is around 50 GW or 50 x 109 W or 50,000,000,000 W. How large would the area of a solar power array need to be to power the enSre state?
Facts needed: Sunlight delivers 1 kW / m2. Solar panel efficiency is about 15%.
(1 mile = 1.6 km)
Solar Powered California PopulaSon is about 40 Million. Typical house uses about 1 kW of power. Peak power demand for state is around 50 GW or 50 x 109 W or 50,000,000,000 W. How large would the area of a solar power array need to be to power the enSre state? About: 11 mi x 11 mi or around 125 square miles (325 square km).
Facts needed: Sunlight delivers 1 kW / m2. Solar panel efficiency is about 15%.
Solar Powered California PopulaSon is about 40 Million. Typical house uses about 1 kW of power. Peak power demand for state is around 50 GW or 50 x 109 W or 50,000,000,000 W. How large would the area of a solar power array need to be to power the enSre state? About: 11 mi x 11 mi or around 125 square miles (325 square km).
Facts needed: Sunlight delivers 1 kW / m2. Solar panel efficiency is about 15%.
Reaching space vs reaching orbit
How much energy is required to reach the height of low-‐earth-‐orbit (r = 1.025 x RE)?
Reaching space vs reaching orbit
How much energy is required to reach the height of low-‐earth-‐orbit (r = 1.025 x RE)?
Calculate the work done: turns out to be a minimum of 1,520 Joules or 0.36 Calories per gram.
Reaching space vs reaching orbit
How much energy is required to reach the height of low-‐earth-‐orbit (r = 1.025 x RE)?
Calculate the work done: turns out to be a minimum of 1,520 Joules or 0.36 Calories per gram.
How much energy is required to enter into low-‐earth-‐orbit (r = 1.025 x RE with v = 7800 m/s)?
Reaching space vs reaching orbit
How much energy is required to reach the height of low-‐earth-‐orbit (r = 1.025 x RE)?
Calculate the work done: turns out to be a minimum of 1,520 Joules or 0.36 Calories per gram.
How much energy is required to enter into low-‐earth-‐orbit (r = 1.025 x RE with v = 7800 m/s)?
Calculate the kineSc energy required to stay in orbit and add it to the number above.
Reaching space vs reaching orbit
How much energy is required to reach the height of low-‐earth-‐orbit (r = 1.025 x RE)?
Calculate the work done: turns out to be a minimum of 1,520 Joules or 0.36 Calories per gram.
How much energy is required to enter into low-‐earth-‐orbit (r = 1.025 x RE with v = 7800 m/s)?
Calculate the kineSc energy required to stay in orbit and add it to the number above.
KE = (1/2) m v2 KE = (1/2) x (0.001 kg) x (7800 m/s)2 = 30,000 Joules or 7.3 Calories per gram
Factor of 20 larger!
GeUng to space is easy. Staying in space is hard!
The inefficiency of rockets The mass of the rocket fuel to reach orbit is about 25 to 50 Hmes the mass of the payload. About 97% of energy is wasted. Book: "It costs about $10,000 to launch a kilogram of anything into orbit. In the near future, commercial companies hope to reduce that price to $1,000 / kg." Space X : Reuse the expensive rocket.
Project Orion Main problem with rockets: you need to liY a heavy rocket (most of the weight is fuel) using chemical reacSons.
Project Orion Main problem with rockets: you need to liY a heavy rocket (most of the weight is fuel) using chemical reacSons.
Nuclear reacSons release about a million Smes more energy per reacSon.
Project Orion
Freeman Dyson
Main problem with rockets: you need to liY a heavy rocket (most of the weight is fuel) using chemical reacSons.
Nuclear reacSons release about a million Smes more energy per reacSon.
Crazy soluHon: propel a ship with a series of nuclear bombs exploding just below the ship!
Search for "project orion" in Google, YouTube, and TED to learn more.
Project was scrapped over concerns about nuclear fallout and the potenSal for accidents.