Physics, often considered the most fundamental of all the sciences, deals with the laws and principles that govern the natural world. From the motion of celestial bodies to the behavior of subatomic particles, physics provides a framework for understanding reality. Yet for many students at the high school and even university level, physics is a source of great difficulty. Despite the beauty and logical structure of the subject, certain concepts routinely challenge students. These difficulties stem from a mix of abstract reasoning, mathematical demands, and the need to visualize phenomena that are not easily observed.
This article explores the physics concepts that students most often struggle to understand, examines why these concepts pose such challenges, and provides insights into how educators and learners can address them.
1. Electricity and Magnetism
Why it's difficult:
Electricity and magnetism are abstract and invisible. Unlike kinematics where motion can be observed directly, students must imagine how electric fields and magnetic fields operate in space.
Common challenges:
- Understanding electric fields and how they exert force at a distance.
- Visualizing field lines and interpreting diagrams.
- Grasping concepts such as potential difference, current, and resistance, and how they interrelate.
- Applying Ohm's Law and Kirchhoff's Rules in complex circuits.
- Understanding electromagnetism - how changing magnetic fields induce currents (Faraday's Law and Lenz's Law).
Why students struggle:
Electric and magnetic fields don't have tangible analogies in everyday life. For instance, the idea that a charge can "feel" a force due to another charge far away is non-intuitive. Additionally, many problems require multi-step calculations that involve both vector and scalar quantities.
2. Waves and Wave Behavior
Why it's difficult:
Waves are fundamentally different from particles. Students often confuse mechanical wave behavior with particle motion, leading to misconceptions.
Common challenges:
- Differentiating between transverse and longitudinal waves.
- Understanding superposition, interference, and standing waves.
- Grasping phase, frequency, amplitude, and their relationship with energy.
- Explaining resonance and its real-world implications.
Why students struggle:
The mathematics of wave behavior (e.g., trigonometric functions, phase angles, and interference patterns) can be complex. Moreover, visualizing how waves overlap and interact is not intuitive without simulations or demonstrations.
3. Newtonian Mechanics (Especially Newton's Laws of Motion)
Why it's difficult:
Although Newton 's Laws are introduced early, they form the foundation for more advanced physics topics and remain challenging in application.
Common challenges:
- Applying Newton 's Second Law in systems with multiple forces (e.g., friction, tension, normal force).
- Understanding action-reaction pairs (Third Law) and correctly identifying them.
- Resolving vector components, especially on inclined planes or circular paths.
- Grasping free-body diagrams and using them effectively.
Why students struggle:
Many students have pre-existing misconceptions from everyday experiences (e.g., heavier objects fall faster, or motion requires constant force). These intuitive but incorrect ideas interfere with learning.
4. Thermodynamics
Why it's difficult:
Thermodynamics introduces abstract, statistical concepts like entropy and internal energy that lack direct sensory experience.
Common challenges:
- Understanding the First and Second Laws of Thermodynamics.
- Interpreting entropy and why it always increases in closed systems.
- Differentiating between heat and temperature.
- Solving problems involving energy transfer, work, and efficiency of heat engines.
Why students struggle:
Heat and energy are often used interchangeably in casual speech, which creates confusion. The microscopic vs. macroscopic viewpoints in thermodynamics also make the subject challenging.
Luckily, the second law of thermodynamics and entropy are not in school syllabus. But the first law alone can be confusing enough for many students.
5. Quantum Mechanics and Atomic Physics
Why it's difficult:
Quantum physics breaks many of the "rules" of classical mechanics and requires students to adopt a probabilistic worldview.
Common challenges:
- Understanding wave-particle duality (e.g., photons, electrons).
- Grasping Heisenberg 's Uncertainty Principle.
- Visualizing orbitals, energy levels, and transitions in atoms.
Why students struggle:
Quantum mechanics contradicts intuition and everyday experience. The math becomes more abstract, and visualizations often involve metaphors rather than concrete imagery.
6. Relativity (Special and General)
Why it's difficult:
Einstein 's theory requires a shift in understanding space, time, and mass - concepts that feel absolute in everyday life.
Think that general relativity cannot be in the school physics syllabus? Think again. For A level (H2) physics, there are exam questions on E = mc2 and gravitational wave. Both are topics in general relativity. But of course, we just get to learn and be tested on the "simple" bits.
Common challenges:
- Grasping E = mc2 and the concept of mass-energy equivalence.
- Visualizing gravitational effects in General Relativity.
Why students struggle:
Relativity demands the acceptance of counterintuitive ideas. The absence of direct, observable phenomena adds to the difficulty.
7. Rotational Motion and Dynamics
Why it's difficult:
Rotational motion builds on linear mechanics but introduces entirely new variables (e.g., angular velocity, torque, moment of inertia).
Common challenges:
- Understanding torque as a rotational analog to force.
- Grasping angular momentum and its conservation.
- Applying Newton 's Laws to rotational systems.
- Using rotational kinematic equations and understanding centripetal forces.
Why students struggle:
It 's easy to misapply linear formulas to rotational systems.
8. Capacitance and Inductance
Why it's difficult:
These topics are often introduced in the later stages of electricity and magnetism, combining abstract concepts with difficult mathematics.
Common challenges:
- Understanding how capacitors (C) and inductors (L) store energy.
- Analyzing RC and RL circuits (where R means resistance) and calculating time constants.
- Interpreting voltage and current changes over time (exponential behavior).
Why students struggle:
The transient behavior in these circuits (i.e., not steady-state) requires a deeper understanding of differential equations or, at least, comfort with time-dependent changes.
9. Fluid Mechanics
Why it's difficult:
Though it appears practical, fluid dynamics involves complex behaviors, especially under varying pressures and flow conditions.
Common challenges:
- Differentiating between static and dynamic fluid scenarios.
- Understanding buoyancy, Archimedes ' Principle, and pressure gradients.
- Grasping viscosity, turbulence, and laminar flow.
Why students struggle:
Many assumptions are hidden in fluid problems. Misapplying these assumptions leads to incorrect conclusions. Visualization is also hard - students can 't "see" how pressure or velocity changes through a pipe.
10. Mathematics in Physics
Why it's difficult:
Although not a concept in itself, math underpins all of physics and is a major source of struggle for many students.
Common challenges:
- Algebraic manipulation of formulas.
- Working with vectors and trigonometry.
- Understanding graphs and interpreting slope and area.
- Using calculus (e.g., for motion, fields, or changing systems).
Why students struggle:
Students often treat math and physics as separate subjects. When their math foundation is weak, they cannot engage deeply with physics problems that require symbolic reasoning or multi-step derivations.
Why These Topics Are Challenging
- Abstract Nature: Many core physics ideas (fields, waves, quantum states) are invisible and intangible.
- Conceptual Shifts: Physics often asks students to replace intuitive understandings with more accurate scientific models.
- Mathematical Demands: Without strong math skills, students struggle to apply concepts correctly.
- Poor Instruction or Materials: Overly theoretical teaching and lack of hands-on experiences can hinder understanding.
- Sequential Learning: Misunderstanding one concept often affects later learning.
Strategies for Overcoming These Difficulties
- Use Simulations and Visualizations
- Encourage Conceptual Understanding First
- Use Analogies and Real-World Examples
- Promote Active Learning
- Strengthen Math Skills in Parallel
- Allow Time for Reflection
Conclusion
Physics is a rigorous and rewarding subject, but it is not without its hurdles. Concepts like electricity and magnetism, waves, thermodynamics, and quantum mechanics routinely challenge students due to their abstract nature, mathematical demands, and counterintuitive ideas. Recognizing these challenges is the first step in addressing them. With effective teaching, appropriate tools, and a growth mindset, even the most difficult physics topics can become accessible - and even enjoyable - for students.
You can learn these concepts and more at Dr Hock's maths and physics tuition.