According to the Official ACT website: “Advanced knowledge in these subjects is not required, but background knowledge acquired in general, introductory science courses is needed to answer some of the questions.” The Physics passages on the ACT Science Test tests what you can do rather than what you already know and if you’ve taken a Physics class at high school, then you will likely already be familiar with most of the scientific vocabulary. However, even if you’re still in Biology or Chemistry, you won’t find the subject matter too intimidating.
Physics covers a wide variety of concepts: mechanics, thermodynamics, electromagnetism, fluids, solids, and optics. Mechanics is the behavior of physical bodies when subject to forces. Thermodynamics is the study of the transfer of heat between materials. Electromagnetism is the study of the interaction of electric currents and magnetic fields. Fluids are substances with no fixed shape, while solids are substances of definite shape and volume. Optics is the study of the behavior of light and radiation.
Everything needed to answer the questions will be presented in the passages. So there will be no questions such as, “what is the second law of thermodynamics?”, unless that answer is to be found explicitly in the given passage. You won’t need to do any difficult Physics computations, either and a calculator is not allowed on the ACT Science Test. The only math that will be required is simple arithmetic: addition, subtraction, multiplication, and division. According to the official ACT guide, “the test emphasizes application of scientific reasoning skills rather than recall of scientific content, skill in mathematics, or reading ability.”
Try reading this Physics-based paragraph to get acquainted with this type of material:
Scientist 1: A black hole is a region in space where the pulling force of gravity is so strong that light is not able to escape. Primordial black holes are thought to have formed in the early universe, soon after the big bang. Stellar black holes form when the center of a very massive star collapses in upon itself. This collapse also causes a supernova, or an exploding star, that blasts part of the star into space. Scientists think supermassive black holes formed at the same time as the galaxy they are in.
Which of the following best describes Scientist 1’s purpose in the paragraph?
(A) to describe how black holes are created
(B) to discuss the dangers of black holes
(C) to point out the differences between stellar and supermassive black holes
(D) to explain how a supernova occurs
This passage tells the reader how black holes are formed, so that is likely what the scientist is most interested in. Note the repeated us of the verb: “thought to have formed,” “form,” and “formed.” (A) is correct.
Remember, we can approach ACT Science passages without any outside Physics knowledge as long as we read the passages carefully, taking notes as we read. It will help to know where to refer back to find specific information to get a correct answer if you use notes. Think of these passages like Physics-themed Reading Test passages.