Q1 · medium · AI-verified
The radius of a nucleus is given by r = r₀A^(1/3), where r₀ = 1.2 × 10⁻¹⁵ m. What is the approximate radius of a nucleus with mass number A = 64?
- 2.4 × 10⁻¹⁵ m
- 9.6 × 10⁻¹⁵ m
- 7.2 × 10⁻¹⁵ m
- 4.8 × 10⁻¹⁵ m
Q2 · hard · AI-verified
The energy of a photon emitted when an electron in a hydrogen atom transitions from n=4 to n=2 is closest to which value? (Use Rydberg energy E₁ = −13.6 eV)
- 0.85 eV
- 3.40 eV
- 2.55 eV
- 1.89 eV
Q3 · hard · AI-verified
A radioactive nucleus has a half-life of 20 days. What fraction of the original sample remains after 80 days?
- 1/32
- 1/4
- 1/8
- 1/16
Q4 · medium · AI-verified
The half-life of a radioactive substance is 20 minutes. What fraction of the original sample remains after 80 minutes?
- 1/32
- 1/8
- 1/4
- 1/16
Q5 · medium · AI-verified
The binding energy per nucleon is maximum for which nucleus?
- Helium-4 (⁴He)
- Uranium-235 (²³⁵U)
- Carbon-12 (¹²C)
- Iron-56 (⁵⁶Fe)