16. What is the energy density ratio of electric and magnetic fields in an electromagnetic wave?
(A) Equal
(B) Electric is twice magnetic
(C) Magnetic is twice electric
(D) Cannot be compared
(E) Depends on frequency

12. What is the relationship between the power P emitted by a blackbody and its temperature T? (A) P ∝ T (B) P ∝ T² (C) P ∝ T³ (D) P ∝ T⁴ (E) P ∝ T⁵

13. In the photoelectric effect, which equation relates stopping voltage U₀ and wavelength λ? (A) hc/(eλ) = U₀ (B) eU₀ = hc/λ (C) U₀ = hc /(eλ) – φ (D) U₀ = φ – hc /(eλ) (E) φ = U₀

14. In a hydrogen atom, what is the energy difference between n = 3 and n = 2? (A) 13.6 eV (B) 1.89 eV (C) 3.4 eV (D) 10.2 eV (E) 12.1 eV

15. An observer measures a clock moving at speed v = 0.6c. What is the time dilation factor γ? (A) 1.0 (B) 1.15 (C) 1.25 (D) 1.50 (E) 2.0

17. A radio station requires a coaxial cable to connect the transmitter to the antenna. The cable consists of an inner conductor with a diameter of 0.2 mm and an outer conductor with a diameter of 2.0 mm, whose thickness is negligible. If the maximum safe potential difference between the conductors is 2.3 kV, what is the maximum charge density the conductors can carry under this safety constraint? (A) 45 μC (B) 50 μC (C) 55 μC (D) 60μC (E) 65 μC

18. A spreading wave packet increases in width over time due to which principle? (A) Second Law of Thermodynamics (B) Conservation of Energy (C) Relativistic Effect (D) Uncertainty Principle (E) Momentum Conservation

19. A particle moves in a non-conservative field but its total energy remains conserved. What is the likely form of the external force? (A) Constant force (B) Position-dependent (C) Velocity-dependent (D) Perpendicular to displacement (E) Time-dependent

20. When a photon undergoes Compton scattering with an electron and is scattered at a 90° angle relative to its original direction, its energy after scattering is half of its original energy. What is the initial wavelength of the photon? (A) 1.33 nm (B) 2.43 nm (C) 1.33 pm (D) 2.43 pm (E) None of the above

1. Consider the situation shown in the figure, where a baseball player slides to a stop on level ground. Using energy considerations, calculate the distance the 65.0-kg baseball player slides, given that his initial speed is 6.00 m/s and the force of friction against him is a constant 450 N. (A)0.6 m (B)1.6 m (C)2.6 m (D)3.6 m (E)4.6 m

2. The Moon orbits Earth each 27.3 days and it has an average distance of 3.84×108 m from the center of Earth. Calculate the period of an artificial satellite orbiting at an average altitude of 1500 km above Earth's surface. The radius of Earth is 6380 km. (A) 0.57 hr (B) 1.9 hr (C) 5.7 hr (D) 19 hr (E) 57 hr