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MCAT Physics Practice Questions (With Step-by-Step Explanations)

by Hawar Palani in MedSchool Tips

For a lot of pre-meds, physics is the section of MCAT prep that brings back the most bad memories. Maybe it's been two years since you took it. Maybe you passed the class by memorizing formulas and never felt like you really understood why they worked.

Here's the good news: MCAT physics is algebra-based, it leans on a fairly predictable set of core concepts, and it rewards reasoning more than heavy math. Once you've practiced enough questions, the patterns start to repeat.

Below you'll find where to get the best practice, which topics deserve your time, and four original worked questions to test yourself right now.

Where Can You Find Good MCAT Physics Practice Questions?

Start with official AAMC materials, add a high-quality question bank for volume, and use free sets to fill gaps. AAMC practice exams and question packs are the closest match to the real test's style, so save some of them for the final weeks of prep. A third-party question bank gives you the volume you need to build speed and pattern recognition before then.

Physics shows up mainly in the Chemical and Physical Foundations of Biological Systems (Chem/Phys) section, as both passage-based questions and standalone discrete questions. Many passages are set in biological or medical contexts, like blood flow, hearing, or vision, and there's no calculator, so the math is designed to be done by hand.

The best MCAT physics practice questions don't just check your final answer. They make you explain why the wrong options are wrong, which is exactly how the explanations below are written.

High-Yield Physics Topics for the MCAT

The AAMC content outline lists everything that can be tested, but these areas come up again and again in practice material:

  • Kinematics and Newton's laws: motion equations, forces, free-body diagrams, friction, inclined planes.
  • Work, energy, and power: conservation of energy, kinetic and potential energy, work done by forces.
  • Fluids: density, buoyancy, pressure, the continuity equation, Bernoulli's equation.
  • Electrostatics and circuits: Coulomb's law, electric fields, Ohm's law, resistors and capacitors in series and parallel.
  • Waves and sound: frequency, wavelength, the Doppler effect, intensity and decibels.
  • Light and optics: refraction, lenses and mirrors, the thin lens equation, magnification.
  • Thermodynamics and atomic physics: heat transfer, laws of thermodynamics, radioactive decay, half-life.

4 Worked MCAT Physics Practice Questions

Try each one before reading the explanation. Use g = 10 m/s², and no calculator.

Question 1: Energy Conservation

A 2 kg block is released from rest at the top of a frictionless ramp 5 m high. What is the block's speed when it reaches the bottom of the ramp?

  • A. 5 m/s
  • B. 7 m/s
  • C. 10 m/s
  • D. 100 m/s

Answer: C. With no friction, all of the block's gravitational potential energy becomes kinetic energy: mgh = ½mv². Mass cancels, leaving v = √(2gh) = √(2 × 10 × 5) = √100 = 10 m/s.

Notice what the question didn't give you: the angle of the ramp. You don't need it, because energy conservation only cares about the change in height. Choice D is what you get if you forget the square root, and choice B (about √50) comes from dropping the 2. The 2 kg mass is a distractor, since mass cancels out of the equation.

Question 2: Fluids and Blood Flow

Blood flows through a horizontal artery. In one segment, plaque narrows the artery to half its original radius. Treating blood as an ideal fluid, how do the flow speed and pressure in the narrowed segment compare with the wider segment?

  • A. Speed doubles; pressure increases
  • B. Speed increases by a factor of 4; pressure decreases
  • C. Speed increases by a factor of 4; pressure increases
  • D. Speed doubles; pressure decreases

Answer: B. The continuity equation says A₁v₁ = A₂v₂. Cross-sectional area depends on radius squared (A = πr²), so halving the radius cuts the area to one quarter. To keep the same volume of fluid moving through per second, the speed must increase by a factor of 4.

For pressure, use Bernoulli's equation. In a horizontal tube, P + ½ρv² stays constant, so where speed goes up, pressure goes down. Choices A and D make the classic radius-versus-area mistake, and choices A and C fall for the intuition that a "squeezed" vessel must have higher pressure.

Watch for this twist: if a question describes blood as viscous or asks about resistance, switch to Poiseuille's law. At a fixed pressure difference, flow rate is proportional to r⁴, so halving a vessel's radius cuts flow to 1/16 of the original. Read the question carefully to see which model it wants.

Question 3: Circuits

A 6 Ω resistor and a 3 Ω resistor are connected in parallel across a 12 V battery. What is the total current drawn from the battery?

  • A. 1.3 A
  • B. 2 A
  • C. 4 A
  • D. 6 A

Answer: D. For two resistors in parallel, the equivalent resistance is (R₁ × R₂) / (R₁ + R₂) = (6 × 3) / (6 + 3) = 18 / 9 = 2 Ω. Using Ohm's law, I = V / R = 12 V / 2 Ω = 6 A.

You can double-check this another way. Each branch of a parallel circuit gets the full 12 V, so the 6 Ω branch carries 12 / 6 = 2 A and the 3 Ω branch carries 12 / 3 = 4 A. Together, that's 6 A. Choices B and C are the individual branch currents, and choice A is what you'd get by incorrectly adding the resistors in series (12 / 9 ≈ 1.3 A). Quick sanity check: the equivalent resistance of a parallel combination is always smaller than the smallest resistor, and 2 Ω is less than 3 Ω.

Question 4: Optics

An object is placed 15 cm in front of a converging lens with a focal length of 10 cm. Which best describes the image?

  • A. Virtual and upright, 30 cm from the lens on the same side as the object
  • B. Real and inverted, 30 cm from the lens on the opposite side, twice the object's height
  • C. Real and inverted, 6 cm from the lens, smaller than the object
  • D. Virtual and upright, 6 cm from the lens, smaller than the object

Answer: B. Use the thin lens equation: 1/f = 1/dₒ + 1/dᵢ. Solving for the image: 1/dᵢ = 1/10 − 1/15 = 3/30 − 2/30 = 1/30, so dᵢ = +30 cm. For a lens, a positive image distance means a real image on the opposite side from the object.

Magnification is m = −dᵢ/dₒ = −30/15 = −2. The negative sign means the image is inverted, and the magnitude of 2 means it's twice the object's height. Choices C and D come from adding the fractions instead of subtracting them (1/10 + 1/15 = 1/6). As a sanity check, an object placed between f and 2f of a converging lens always forms a real, inverted, enlarged image beyond 2f.

How to Solve MCAT Physics Without a Calculator

The math on test day is meant to be manageable, but only if you have a few habits locked in.

Round Strategically

Use g = 10 m/s² unless told otherwise, and round awkward numbers to friendly ones. Answer choices are usually spread far enough apart that a close estimate gets you to the right one.

Use Scientific Notation

Convert large and small numbers to scientific notation before multiplying or dividing. It's much faster and helps you avoid mistakes with decimal places.

Think in Proportions

Many questions ask what happens when one variable changes, like Question 2. If you know a quantity depends on r² or r⁴, you can answer without plugging in any numbers.

Check Your Units

If your answer comes out in the wrong units, something went wrong. Unit analysis can also help you rebuild a formula you only half-remember.

What Most Students Get Wrong About Physics Practice

The biggest mistake is memorizing formulas without understanding them. The MCAT often gives you a familiar concept in an unfamiliar setting, and if you only know the formula, it's hard to recognize when to use it. Focus on why each relationship works.

The second mistake is doing only discrete questions. Standalone questions are great for drilling concepts, but much of the real exam is passage-based. Make sure your practice includes passages that mix physics with biology, like the blood flow example above.

The third mistake is skipping review. The value of MCAT physics practice questions comes from understanding every miss and every lucky guess. Keep an error log noting the concept, why you missed it, and what you'll do differently next time.

The fourth is saving full-length exams for the very end. Physics under time pressure, mixed in with chemistry and biochemistry, feels different from untimed practice. For an early full-length that costs nothing, the free MCAT full-length on MedSchoolGuru shows how your physics holds up mixed in with the rest of Chem/Phys. Plan your full-lengths across your prep (we cover timing in how many practice tests to take before the MCAT).

Getting More Physics Practice That Sticks

Four questions are a start, but real improvement comes from steady, high-volume practice with detailed explanations. The MCAT Question Bank from MedSchoolBro includes 3,000+ AAMC-style questions and 4 full-length exams, so you can drill physics topics and then see how they hold up in a full test. If the underlying concepts still feel shaky, The Complete MCAT Guide from MedSchoolBro gives you a 225-page review to rebuild your foundation first.

 

Frequently Asked Questions

How much physics is on the MCAT? Physics is tested mainly in the Chem/Phys section, alongside general chemistry, organic chemistry, and biochemistry. The AAMC's content outline lists the approximate share of each discipline, so check it as you plan your study time. Physics concepts also show up in biological contexts, like circulation and vision.

Can you use a calculator on the MCAT? No. Calculators aren't allowed, so the math is designed to be done by hand with estimation, scientific notation, and simple fractions. Practicing without a calculator from the start makes test day feel much more familiar.

Do you need calculus for MCAT physics? No. MCAT physics is algebra-based, with some basic trigonometry for things like vectors and inclined planes. The challenge is applying concepts to new situations, not complex math.

How many MCAT physics practice questions should I do? There's no magic number. Focus on doing questions consistently across your prep, reviewing every explanation carefully, and including passage-based questions and full-length exams. Quality of review matters more than raw volume.

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What Gluconeogenesis Is Made From Lactate and the Cori Cycle Red blood cells (no mitochondria) and exercising muscle produce lactate. Lactate travels to the liver, where lactate dehydrogenase converts it back to pyruvate, and gluconeogenesis turns it into glucose that returns to the tissues. That loop is the Cori cycle. It costs the liver more ATP than glycolysis produces in the muscle, so it's a net energy expense for the body. Alanine and Other Glucogenic Amino Acids In the glucose-alanine cycle, muscle converts pyruvate to alanine by transamination, sends it to the liver, and the liver converts it back to pyruvate. As a bonus, this moves nitrogen to the liver for the urea cycle. Other glucogenic amino acids enter as pyruvate or as TCA intermediates that become oxaloacetate. Leucine and lysine are purely ketogenic and can't be used. Glycerol When triglycerides are broken down in adipose tissue, the glycerol backbone goes to the liver. Glycerol kinase phosphorylates it to glycerol-3-phosphate, which is oxidized to DHAP and enters the pathway at the triose phosphate level. What Can't Be Used: Even-Chain Fatty Acids This is a favorite trap. Even-chain fatty acids cannot produce a net gain of glucose. Their breakdown yields acetyl-CoA, and pyruvate dehydrogenase is irreversible, so acetyl-CoA can't become pyruvate. Acetyl-CoA entering the TCA cycle loses two carbons as CO2, so there's no net oxaloacetate gained either. The exception is odd-chain fatty acids, whose final propionyl-CoA becomes succinyl-CoA (a step that requires vitamin B12) and can feed gluconeogenesis. Fatty acid oxidation still helps indirectly by supplying ATP and the acetyl-CoA that activates pyruvate carboxylase. How Gluconeogenesis Is Regulated Hormonal Control Glucagon (and epinephrine) raise cAMP and activate protein kinase A in the liver. PKA does two important things: it lowers fructose-2,6-bisphosphate levels by phosphorylating the bifunctional enzyme PFK-2/FBPase-2, and it inactivates liver pyruvate kinase. Both changes favor gluconeogenesis over glycolysis. Cortisol increases transcription of gluconeogenic enzymes like PEPCK and mobilizes amino acids from muscle. Insulin does the opposite on every front. Fructose-2,6-Bisphosphate: The Switch Fructose-2,6-bisphosphate activates PFK-1 and inhibits fructose-1,6-bisphosphatase. High levels (fed state, insulin) push the liver toward glycolysis. Low levels (fasting, glucagon) push it toward gluconeogenesis. If you understand this one molecule, you understand reciprocal regulation. Allosteric Signals Acetyl-CoA activates pyruvate carboxylase and inhibits pyruvate dehydrogenase, steering pyruvate toward glucose instead of the TCA cycle. AMP inhibits fructose-1,6-bisphosphatase while activating PFK-1. The logic is always the same: low energy favors glycolysis, high energy and low blood glucose favor gluconeogenesis. What Most Students Get Wrong About Gluconeogenesis The biggest mistake is treating it as glycolysis in reverse and stopping there. Gluconeogenesis MCAT questions rarely ask about the shared reversible steps. They ask about the bypass enzymes, where they are, and what controls them. The second mistake is the fatty acid trap. Students know fat is stored energy, so they assume it can become glucose. Even-chain fatty acids can't make net glucose, but glycerol and odd-chain fatty acids can. Expect answer choices built around that exact distinction. The third mistake is forgetting tissue differences. Muscle lacks glucose-6-phosphatase, so it can't export glucose. The liver can. When a passage mentions a muscle-specific enzyme deficiency versus a liver one, that difference usually decides the answer. A related classic: heavy alcohol use raises the NADH/NAD+ ratio, which pushes pyruvate toward lactate and oxaloacetate toward malate, starving gluconeogenesis and causing hypoglycemia. Making Metabolic Pathways Stick Gluconeogenesis is a pathway you need to recall fast and apply under pressure, which is exactly where visual, repeated review pays off. The MCAT Flashcard Set from MedSchoolBro gives you 477 illustrated cards, so enzymes, regulators, and pathway connections become pictures you can recall instead of lists you reread. When you're ready to test that recall in passage format, the MCAT Question Bank from MedSchoolBro has 3,000+ AAMC-style questions to practice applying metabolism under real test conditions.   Frequently Asked Questions What is the rate-limiting enzyme of gluconeogenesis? Fructose-1,6-bisphosphatase is generally taught as the key regulated (rate-limiting) step. It's inhibited by AMP and fructose-2,6-bisphosphate, and it mirrors PFK-1 in glycolysis. Pyruvate carboxylase is also heavily regulated, mainly through activation by acetyl-CoA. Can fatty acids be converted into glucose? Not even-chain fatty acids, because their acetyl-CoA can't be converted back to pyruvate and gives no net oxaloacetate in the TCA cycle. Odd-chain fatty acids can contribute through propionyl-CoA, and the glycerol from triglycerides is a genuine gluconeogenic substrate. On the MCAT, "fat can't become glucose" really means even-chain fatty acids. Why can't muscle perform gluconeogenesis to raise blood glucose? Muscle lacks glucose-6-phosphatase, so it can't remove the final phosphate and release free glucose into the blood. Instead, muscle sends lactate and alanine to the liver, which does the gluconeogenesis. That's the whole point of the Cori and glucose-alanine cycles. How does gluconeogenesis connect to glycogen metabolism? Both maintain blood glucose during fasting and are activated by glucagon. Glycogen breakdown handles the early hours, and gluconeogenesis takes over as liver glycogen runs low. Gluconeogenesis MCAT questions often ask which source dominates at a given point in a fast, so know the general timeline.

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