NEET Atoms and Nuclei — Set 16

Question 1

Why is nuclear fusion more likely to release energy when light nuclei are involved?

Accepted Answer

In light nuclei (A < 30), the binding energy per nucleon is lower. When they fuse into a heavier nucleus, the binding energy per nucleon increases, releasing energy as the final system is more tightly bound.

Question 2

The radius of a nucleus is $ 6.0 \times 10^{-15} \, \text{m} $. What is its approximate mass number? (Given $ R_0 = 1.2 \times 10^{-15} \, \text{m} $)

Accepted Answer

$ R = R_0 A^{1/3} $. $ 6.0 \times 10^{-15} = 1.2 \times 10^{-15} \times A^{1/3} $. $ A^{1/3} = \frac{6.0}{1.2} = 5 $. $ A = 5^3 = 125 $.

Question 3

What is the approximate radius of a nucleus with mass number 8? (Given $ R_0 = 1.2 \times 10^{-15} \, \text{m} $)

Accepted Answer

The radius of a nucleus is given by $ R = R_0 A^{1/3} $, where $ A = 8 $. $ A^{1/3} = 8^{1/3} = 2 $. $ R = 1.2 \times 10^{-15} \times 2 = 2.4 \times 10^{-15} \, \text{m} $.

NEET Physics: Atoms and Nuclei — Practice Set 16

Q1. Why is nuclear fusion more likely to release energy when light nuclei are involved?

Q2. The radius of a nucleus is \( 6.0 \times 10^{-15} \, \text{m} \). What is its approximate mass number? (Given \( R_0 = 1.2 \times 10^{-15} \, \text{m} \))

Q3. What is the approximate radius of a nucleus with mass number 8? (Given \( R_0 = 1.2 \times 10^{-15} \, \text{m} \))

Q4. What is the energy equivalent of \( 1 \, \text{kg} \) of matter in Joules? (Given \( c = 3 \times 10^8 \, \text{m/s} \))

Q5. What is the mass defect of a nucleus with binding energy \( 93.15 \, \text{MeV} \)? (Given \( 1 \, \text{u} = 931.5 \, \text{MeV/c}^2 \))

Q6. What is the main source of energy in nuclear reactors?

Q7. What is the radius of a nucleus with mass number 108? (Given \( R_0 = 1.2 \times 10^{-15} \, \text{m} \))

Q8. What is the energy equivalent of \( 0.5 \, \text{g} \) of matter in Joules? (Given \( c = 3 \times 10^8 \, \text{m/s} \))

Q9. InEinstein's mass-energy equivalence, what does the term \( c^2 \) represent?

Q10. What is the mass defect of a nucleus if its binding energy is \( 186 \, \text{MeV} \)? (Given \( 1 \, \text{u} = 931.5 \, \text{MeV/c}^2 \))