Physics Cheat Sheet 2026

The 30 highest-yield Physics facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. Which statement best describes the third law of thermodynamics? → The entropy of a perfect crystal approaches zero as temperature approaches absolute zero
2. A diverging lens always produces images that are: → Virtual and upright
3. On the Moon, where g ≈ 1.6 m/s², a 60 kg person would weigh approximately: → 96 N
4. What role does ethics play in Waves and Sound practice? → It guides professional conduct and protects stakeholders
5. What is the beat frequency heard when two tuning forks vibrate at 440 Hz and 444 Hz simultaneously? → 4 Hz
6. The COP (coefficient of performance) of a refrigerator is defined as: → Q_cold/W
7. Which of the following is an example of a longitudinal wave? → Sound
8. Which condition must be true for an object to be in static equilibrium? → Net force is zero and net torque is zero
9. What is the buoyant force on a submerged object equal to, according to Archimedes' principle? → Weight of fluid displaced
10. What is the relationship between theory and practice in Motion and Forces? → Theory provides the foundation; practice applies it to real situations
11. Bernoulli's principle relates which quantities in steady fluid flow? → Pressure, velocity, and height
12. A block slides down a frictionless incline of height 5 m. What is its speed at the bottom? (Take 𝑔=9.8m/s2). → 10 m/s
13. A gas absorbs 500 J of heat and does 200 J of work. What is the change in its internal energy? → 300 J
14. The law of reflection states that the angle of incidence equals the angle of reflection, both measured relative to the: → Normal to the surface
15. A rigid rod is pivoted at one end. A force of 20 N is applied perpendicular to the rod at a distance of 1.5 m from the pivot. What is the torque produced? → 30 N·m
16. Why is continuing education important in Motion and Forces? → To stay current with evolving standards and practices
17. The power dissipated in a resistor R carrying current I is expressed as: → P = I²R
18. If 500 J of heat is added to a system and the system does 200 J of work, what is the change in internal energy? → 300 J
19. A geosynchronous satellite orbits Earth with a period of: → 24 hours
20. What is a nuclear chain reaction? → Self-sustaining series of fissions where released neutrons trigger more fissions
21. Which of the following materials has the highest electrical conductivity? → Copper
22. What is the relationship between theory and practice in Waves and Sound? → Theory provides the foundation; practice applies it to real situations
23. Why is continuing education important in Motion and Forces? → To stay current with evolving standards and practices
24. How does documentation support quality in Motion and Forces? → It creates records, ensures consistency, and enables improvement
25. In single-slit diffraction, the central maximum is how wide compared to the other maxima? → Twice as wide
26. What is the relationship between theory and practice in Energy and Work? → Theory provides the foundation; practice applies it to real situations
27. What principle allows a hydraulic press to lift heavy loads with a small input force? → Pascal's Law
28. A proton moves east in a uniform magnetic field directed north. In which direction is the magnetic force on the proton? → Upward
29. Polarization is a property unique to which type of wave? → Transverse waves only
30. What role does ethics play in Energy and Work practice? → It guides professional conduct and protects stakeholders