Things you wish you knew when you started to study physics?

[Rodney182]

Hi there! I'm a new member trying to self-study physics.

I apologise if this is in the wrong place on the forum. Feel free to lock or move the thread if so.

What are some things you wish you knew when you started learning physics? Or things about the world of science/physics that you wish someone had told you?

I am just trying to connect with new people about this passion of mine and get some opinions.

 

[PeroK]

Three pieces of advice:

Forget all popular science sources.

It's up to you to change the way you think. Science is not going to change to accommodate your preferences.

Be prepared to work hard.

 

[Rodney182]

Three pieces of advice:

Forget all popular science sources.

It's up to you to change the way you think. Science is not going to change to accommodate your preferences.

Be prepared to work hard.

What would be popular science sources? Do you mean generic pop-science books/documentaries?

 

[PeroK]

What would be popular science sources? Do you mean generic pop-science books/documentaries?

Yes, everything that is not a textbook or equivalent academic source.

 

[berkeman]

Welcome to PF.

What are some things you wish you knew when you started learning physics?

One of the most useful tips that I learned early in my study of Physics and Engineering is to carry units along in the equations you are writing and solving. If you ensure that your units match between terms and across the equal sign, it goes a long way toward helping you understand what is going on and avoiding mistakes.

It also helps in unit conversions, since you can multiply anything by "1" and not change its value. So to change units between, say, cm and meters, you multiply by $1 = \frac{1m}{100cm}$ so that the units of cm cancel out and you are left with units of meters and the corresponding new number.

 

[Rodney182]

Welcome to PF.


One of the most useful tips that I learned early in my study of Physics and Engineering is to carry units along in the equations you are writing and solving. If you ensure that your units match between terms and across the equal sign, it goes a long way toward helping you understand what is going on and avoiding mistakes.

It also helps in unit conversions, since you can multiply anything by "1" and not change its value. So to change units between, say, cm and meters, you multiply by $1 = \frac{1m}{100cm}$ so that the units of cm cancel out and you are left with units of meters and the corresponding new number.

Ty! I will keep this in mind.

 

[CrysPhys]

What are some things you wish you knew when you started learning physics? Or things about the world of science/physics that you wish someone had told you?

What I'm about to say doesn't fall into the category of "what I wish I had known, or what I wish someone had told me", because it's what I actually did, what came naturally to me. Also what I'm about to say will be counter to the advice given by many here.

When you're starting out, don't drown yourself in math. Focus on observations and experiments. You've given us no background (such as age, education, and experiences). But you don't need expensive equipment to get started. Build mechanical, electrical, and electronic apparatus. Hook them up to computers. If you've got the money, buy basic instruments such as a microscope, telescope, and a balance. Don't just read physics problems in textbooks. Do actual hands-on observations and experiments. Try out a variety of fields. You'll find out what sparks your passion, and what puts you to sleep. Develop physical intuition.

 

[symbolipoint]

What CrysPhys says in post #7 could be restated as, One should have well designed laboratory exercises. These are made available to college and university Physics students.

As to absolute beginners in Physics, much of the ideas and skills necessary would also be introduced very early in the one or two beginning courses (meaning, going to school, enrolling in and attending the courses). Basic algebra is necessary, at least up through all of Intermediate Algebra. Basic Trigonometry is also necessary, and your department may enforce these by directing the beginning students to enroll into a remedial course just to make students who are lacking to review and rebuild these; and students who do not follow that plan would be administratively dropped from their beginning Physics course.

 

[CrysPhys]

What CrysPhys says in post #7 could be restated as, One should have well designed laboratory exercises. These are made available to college and university Physics students.

No, your restatement is actually counter to the spirit of my Post #7. I'm an advocate of what some writers have expressed as "curiosity-driven science" . They aren't structured laboratory exercises geared towards college and university physics students.

Again, we lack key background information on the OP. But if you can't afford a microscope, start with a magnifier. If you can't afford a telescope, start with a pair of binoculars. If you can't afford an oscilloscope, start with a multimeter. ....

Some science can be done without specialized equipment at all, aptly named "kitchen science". Interested in phase transformations? Start by attempting to grow rock candy crystals from sucrose (ordinary sugar) solutions in water. Compare that with attempting to grow rock salt crystals from sodium chloride (ordinary table salt) solutions in water.

Whenever a newbie posts, "I've developed a passion for physics.", I often ask, "What triggerred this passion?". And quite often I get no answer, a nebulous answer, or even a hostile response. I'm looking for specific, concrete triggers. To me, passion for physics (or other science) starts with a moment (or moments) of wonderment. And the most glorious moments are often serendipitous.

 

[Choppy]

Things I would tell my first year undergrad self...

• Start thinking now about your long-term plan. Physics is an academic subject, and sure, you want to go as far as you can with it, but the odds of finding a tenured position are very much against you, so as you're selecting courses, think about what you want to do if and when you leave academia. What kind of skills do you want to develop? What kind of work will you want to do?
• A school name is not nearly as important has how well you perform at the school you're at. If you fail out of a brand name/ivy league school, you've still failed out.
• Explore. There are a lot of sub-fields of physics. Stretch yourself and don't just assume that because you enjoyed the popular science related on one sub-field that it's the only option for you.
• Kindle your passion. Assignments will take up all of your time if you let them, but it's also important to make time for your own interests. Go to departmental talks, attend undergrad conferences, read papers (even if you don't understand them).
• Building on that last point, take on some of your own projects. Try some coding. Do some physical experiments. Invest in a telescope.
• Make friends with other people who share your passion. It's easy to lock yourself in a cubicle of solitude with earbuds and a textbook, but it's amazing how much learning happens when you're just chatting with other people, or working on problems together. If they're smarter than you... all the better.
• Get involved in research of some sort. Summer research positions, thesis projects, etc. It doesn't have to be in the field you ultimately want to study. Take advantage of the opportunities in front of you.
• Apply for any scholarship you qualify for.
• Take good care of yourself.

 

[berkeman]

Build mechanical, electrical, and electronic apparatus. Hook them up to computers.

Building on that last point, take on some of your own projects. Try some coding. Do some physical experiments. Invest in a telescope.

I do have advice similar this that I give to Engineering students, but it may apply to Physics students as well. I agree that building projects helps a lot in your learning. When you build a project (circuit board, 3-D printed mechanical assembly, integrated circuit + computer interface and program, etc.), you run into all kinds of roadblocks that you need to deal with. You end up saying to yourself, "Wait a minute, they never warned me about this, they never taught me this...", and you learn to ask the right questions (of yourself and your instructors) when you are learning new things.

In undergrad I built a 2-D laser deflection mirror assembly for audio frequencies (picture dorm parties with Boston and Pink Floyd playing over the stereos), a digital alarm clock and an analog 5V & +/-12V power supply (UL compliant). One of my friends (who was amazing) built an AM/FM radio and simple 8-bit computer from scratch (discrete transistors and SSI ICs). You get the idea.

 

[Herman Trivilino]

See if you can find a used copy of A Guide to Introductory Physics Teaching by Arnold B. Arons. Each section title of Chapter 1 will clue you in to which topics to study -- you'll likely need secondary sources for those.