Praxis Physics Practice Test
Praxis Physics (5266) practice centers on explaining physical systems with mathematical models and applying core principles to quantitative problems. The available question bank samples mechanics, thermal physics, fluids, oscillations, and electricity. Tasks include calculating forces and energy, interpreting pressure relationships, and connecting equations to the behavior of idealized physical systems.
Exam overview
About the Praxis Physics Exam
Physics problem solving requires selecting a suitable model, identifying known and unknown quantities, and tracking units and sign conventions through calculations. Mechanics questions can involve gravitational force, mechanical energy, torque, rotational motion, and simple harmonic motion; solving them depends on distinguishing scalar from vector quantities and recognizing conservation relationships. Thermal and fluid problems call for reasoning about ideal gases, absolute temperature, pressure, depth, and density. Electricity questions test the relationship between charge, electric field, force, resistance, voltage, and current, including how series circuits behave. For teaching practice, a useful skill is explaining why an equation applies, stating assumptions such as an ideal source or small oscillations, and checking whether a computed result has a physically reasonable magnitude and unit.
Sample Practice Questions
Review a selection from this exam's published US Practice Tests practice bank.
A sealed rigid container holds an ideal gas. Its absolute temperature increases from 300 K to 450 K. What happens to the gas pressure?
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Correct answer: CAt fixed volume and amount of gas, the ideal-gas law implies P/T is constant. Therefore P₂/P₁ = 450/300 = 1.5.
A hydraulic lift has a small piston with area 0.010 m² and a large piston with area 0.50 m². If a force of 20 N is applied to the small piston, what ideal force acts on the large piston?
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Correct answer: DPascal’s principle gives equal pressure: F₁/A₁ = F₂/A₂. Thus F₂ = 20 × (0.50/0.010) = 1000 N.
A charge of 2.0 μC is placed in a uniform electric field of magnitude 3.0 × 10⁴ N/C. What is the magnitude of the electric force on the charge?
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Correct answer: BThe electric force magnitude is F = |q|E. With q = 2.0 × 10⁻⁶ C, F = (2.0 × 10⁻⁶)(3.0 × 10⁴) = 6.0 × 10⁻² N.
A 12 Ω resistor and a 4.0 Ω resistor are connected in series to an ideal 16 V source. What is the current in the circuit?
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Correct answer: BIn series, resistances add: Rtotal = 12 Ω + 4.0 Ω = 16 Ω. Ohm’s law gives I = V/R = 16 V/16 Ω = 1.0 A.
A 2.0 kg object moving at 6.0 m/s has a total mechanical energy of 46 J. What is its gravitational potential energy relative to the chosen reference level?
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Correct answer: AIts kinetic energy is (1/2)mv² = (1/2)(2.0)(6.0²) = 36 J. Total mechanical energy is the sum of kinetic and potential energy, so the potential energy is 46 J − 36 J = 10 J.
A uniform solid disk rotates about its central axis. If its moment of inertia is I and its angular speed is ω, what is its rotational kinetic energy?
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Correct answer: CRotational kinetic energy is K_rot = ½Iω², analogous to translational kinetic energy ½mv².
A 2.0 kg object is at rest on a horizontal surface. What is the magnitude of the gravitational force on it? Use g = 9.8 m/s².
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Correct answer: CThe gravitational force (weight) is mg = (2.0 kg)(9.8 m/s²) = 19.6 N.
How to use this practice test
Access the free practice set to answer up to 20 randomly selected questions from the 50-question bank. After the session, review the results to identify which calculations or concepts need attention, such as torque, gas pressure, circuit current, or fluid pressure. Rework missed problems by writing the governing relationship and checking units.
Preparation tips
- For mechanics problems, sketch forces or lever arms and distinguish translational energy from rotational kinetic energy before substituting values.
- Practice rearranging ideal-gas and hydrostatic-pressure relationships; use kelvins for absolute temperature and separate gauge pressure from absolute pressure.
- For circuit and electric-field calculations, write the relevant relationships first, such as Ohm’s law or electric force as charge times field, then track units.
- Review simple harmonic motion by connecting mass and spring constant to period, and check that the result has units of time.
- After each practice session, sort missed questions by concept and solve them again with an equation, substitution, units, and a brief reasonableness check.