SAT Physics Subject Test Information

How's your grasp of thermodynamics? Optics? Magnetics? If your answer is anywhere from "Great!" to "Fantastic!" then I'd recommend showing off that killer brain of yours with the SAT Physics Subject Test. This test is not part of the SAT Reasoning Test, the popular college admissions exam. Nope. This is one of the many SAT Subject Tests, exams designed to showcase your particular talents in all sorts of fields.

SAT Physics Subject Tests Basics

Before you register for this test, here are the basics about how you'll be tested:

• 60 minutes
• 75 multiple-choice questions
• 200-800 points possible
• Calculators are not permitted on the test, but would be unnecessary anyway.

SAT Physics Subject Test Content

Before you go plunging in headfirst, it's a good idea to wrap your head around the content of the test. What exactly will you be expected to know? Here's the stuff on which you'll be questioned:

Mechanics: Approximately 27-32 questions

• Kinematics: (Velocity, acceleration, motion in one dimension, and motion of projectiles)
• Dynamics: (Force, Newton’s laws, statics, and friction)
• Energy and Momentum: (Potential and kinetic energy, work, power, impulse, and conservation laws)
• Circular Motion: (Uniform circular motion and centripetal force)
• Simple Harmonic Motion: (Mass on a spring and the pendulum)
• Gravity: (law of gravitation, orbits, and Kepler’s laws)

Electricity and Magnetism: Approximately 13-18 questions

• Electric Fields, Forces, and Potentials: (Coulomb’s law, induced charge, field and potential of groups of point charges, and charged particles in electric fields)
• Capacitance: (Parallel-plate capacitors and time-varying behavior in charging/ discharging)
• Circuit Elements and DC Circuits: (Resistors, light bulbs, series and parallel networks, Ohm’s law, and Joule’s law)
• Magnetism: (Permanent magnets, fields caused by currents, particles in magnetic fields, Faraday’s law, and Lenz’s law)

Waves and Optics: Approximately 11-15 questions

• General Wave Properties: (Wave speed, frequency, wavelength, superposition, standing wave diffraction, and Doppler effect)
• Reflection and Refraction: (Snell’s law and changes in wavelength and speed
• Ray Optics: (Image formation using pinholes, mirrors, and lenses)
• Physical Optics: (Single-slit diffraction, double-slit interference, polarization, and color)

Heat and Thermodynamics: Approximately 5-8 questions

• Thermal Properties: (Temperature, heat transfer, specific and latent heats, and thermal expansion)
• Laws of Thermodynamics: (First and second laws, internal energy, entropy, and heat engine efficiency)

Modern Physics: Approximately 5-8 questions

• Quantum Phenomena: (Photons and photoelectric effect)
• Atomic: (The Rutherford and Bohr models, atomic energy levels, and atomic spectra)
• Nuclear and Particle Physics: (Radioactivity, nuclear reactions, and fundamental particles)
• Relativity: (Time dilation, length contraction, and mass-energy equivalence)

Miscellaneous: Approximately 3-8 questions

• General: (History of physics and general questions that overlap several major topics)
• Analytical Skills: (Graphical analysis, measurement, and math skills)
• Contemporary Physics: (Astrophysics, superconductivity, and chaos theory)

SAT Physics Subject Test Skills

Above is the material you need to know. Here is how you'll need to know it. How in-depth are the questions? Will you be using reasoning or just a basic comprehension of the info? Check it out:

• Recall of Facts: Approximately15 - 25 Questions. Here, you'll be tested on whether or not you remember a definition, can identify a term, or can otherwise shell out important Physics knowledge.
• Single Concept Problem: Approximately 30 - 40 Questions. Many of the questions on the test will relate to only one concept at a time.
• Multiple-Concept Problem: Approximately 15 – 25 Questions. Quite a few of the questions will gauge your ability to consider more than one issue at a time.

Why Take the SAT Physics Subject Test?

I touched on this at the beginning, but truthfully, the one reason you'll want to take the SAT Physics Subject Test is to show off a complex Physics background if you're headed into a science-related field where these skills would be prized. A few science-related majors like Engineering or Aeronautics may even require the test.

How to Prepare for the SAT Physics Subject Test

You'll definitely need to have at least one college-level Physics class to score high on this test along with appropriate algebra and trigonometry classes. You'll need to have logged many hours in the lab in order to understand some of the concepts and know your Physics textbook inside and out. I'd recommend checking with your Physics teacher in school for recommended reading if you'd like some practice questions. In addition, there are some free practice questions on the College Board site, along with the answers.

Sample SAT Physics Subject Test Question

This question comes from the College Board's free practice questions. The writers have ranked the questions from 1 to 5 where 1 is the least difficult. The question below is ranked as a 3.

In a given process, 12 joules of heat is added to an ideal gas and the gas does 8 joules of work. Which of the following is true about the internal energy of the gas during this process?

(A) It has increased by 20 joules.
(B) It has increased by 4 joules.
(C) It has not changed.
(D) It has decreased by 4 joules.
(E) It has decreased by 20 joules.

Answer: Answer choice (B) is correct. It has increased by 4 joules. According to conservation of energy, as expressed by the first law of thermodynamics, adding 12 joules of heat to an ideal gas would increase the internal energy of the gas by 12 joules. However, the internal energy of the gas would decrease by 8 joules if that 8 joules is converted to work done by the gas.

So the net change in the internal energy of the gas is 12 joules – 8 joules, which is a net increase of 4 joules.