Neco 2022 Physics Question 9

Practice objective / multiple choice question 9 from the 2022 Neco Physics examination.

Neco 2022 Physics Objective / Multiple Choice Hard Difficulty
Question 9 NECO • 2022 • PHYSICS • objective

A pure sample of the isotope \(^{238}\text{X}\) of mass \(2.0\ \text{g}\) decays by \(\alpha\) emission to \(^{234}\text{Y}\) with a half‑life of \(4.5\times10^{9}\ \text{yr}\). Each \(\alpha\) particle carries a kinetic energy of \(4.7\ \text{MeV}\).\n\n(i) Compute the activity of the sample in becquerels.\n\n(ii) Determine the power (in watts) released by the sample.\n\n(iii) The sample is placed in a shield that reduces the effective activity to \(1\%\) of its original value and absorbs \(60\%\) of the \(\alpha\) particles' energy. What is the net power after shielding?

Answer Options

A. Activity ≈ 1.2×10^4 Bq; Power ≈ 9.5×10^-9 W; Net power after shielding ≈ 3.8×10^-11 W
B. Activity ≈ 2.5×10^5 Bq; Power ≈ 1.9×10^-7 W; Net power after shielding ≈ 7.4×10^-10 W
C. Activity ≈ 3.6×10^4 Bq; Power ≈ 2.8×10^-8 W; Net power after shielding ≈ 1.1×10^-10 W
Correct Answer D. Activity ≈ 2.5×10^4 Bq; Power ≈ 1.9×10^-8 W; Net power after shielding ≈ 7.4×10^-11 W
Correct Answer
D
Correct Option:
Activity ≈ 2.5×10^4 Bq; Power ≈ 1.9×10^-8 W; Net power after shielding ≈ 7.4×10^-11 W

About This Question

This is Neco 2022 Physics Question 9. It is one of the objective questions from the 2022 Neco Physics examination.

Difficulty level: Hard .

View More Neco 2022 Physics Questions More Neco Practice Questions Back to Questions

Master the Exam!

You've seen a preview, but there are thousands more questions plus AI tutor to break down complex solutions.

Unlock Full Access Available for Android & Windows
Chat with Support