IB DP Physics Mock Exam SL Paper 1A Set 3 - 2025 Syllabus

IB DP Physics Mock Exam SL Paper 1A Set 3

Prepare for the IB DP Physics Mock Exam SL Paper 1A Set 3 with our comprehensive mock exam set 3. Test your knowledge and understanding of key concepts with challenging questions covering all essential topics. Identify areas for improvement and boost your confidence for the real exam

IB DP Physics Mock Tests -All Sets

Question

Energy level transitions E₁, E₂, E₃, E₄ in an atom.

Which emits photon with longest wavelength?

(A) E₁
(B) E₂
(C) E₃
(D) E₄

▶️ Answer/Explanation

Detailed solution

Photon wavelength λ ∝ 1/energy
Longest wavelength ⇒ smallest energy transition
From the energy level diagram, E₄ represents the smallest energy gap (typically between closely spaced higher levels)
✅ Answer: (D) E₄

Question

Fusion: 0.024 u mass defect per H nucleus. Fission: 0.48 u mass defect per U nucleus. Find energy/mass ratio H:U.

(A) 0.050
(B) 0.426
(C) 2.35
(D) 20.0

▶️ Answer/Explanation

Detailed solution

Energy released ∝ mass defect
Energy per unit mass = (mass defect)/(total mass)
Fusion: H mass ≈ 2+3 = 5 u, energy/mass = 0.024/5 = 0.0048
Fission: U mass ≈ 235 u, energy/mass = 0.48/235 ≈ 0.00204
Ratio = 0.0048/0.00204 ≈ 2.35
✅ Answer: (C) 2.35

Question

Stars X and Y have same surface temperature. Star X has radius R and distance d. Star Y has distance d/2 and apparent brightness double that of X. What is Y’s radius?

(A) \( \frac{R}{2} \)
(B) \( \frac{\sqrt{2}}{2}R \)
(C) \( R \)
(D) \( 2R \)

▶️ Answer/Explanation

Detailed solution

Apparent brightness b ∝ L/d² where L is luminosity
Luminosity L ∝ R²T⁴ (Stefan-Boltzmann law)
Same temperature ⇒ L ∝ R²
For star X: bₓ ∝ R²/d²
For star Y: bᵧ ∝ Rᵧ²/(d/2)² = 4Rᵧ²/d²
Given bᵧ = 2bₓ ⇒ 4Rᵧ²/d² = 2(R²/d²)
4Rᵧ² = 2R² ⇒ Rᵧ² = R²/2 ⇒ Rᵧ = R/√2 = (√2/2)R
✅ Answer: (B) \( \frac{\sqrt{2}}{2}R \)

IB DP Physics Mock Exam SL Paper 1A Set 3 - 2025 Syllabus