Difficulty: Easy
Correct Answer: 1/1836 of the proton mass
Explanation:
Introduction / Context:
Mass ratios among subatomic particles are constants used throughout atomic physics, spectroscopy, and accelerator calculations. The electron-to-proton mass ratio is a widely memorized benchmark value.
Given Data / Assumptions:
Concept / Approach:
Divide electron mass by proton mass to obtain the ratio. The accepted approximate ratio is m_e/m_p ≈ 1/1836 (more precisely ≈ 1/1836.15). Hence, the electron is much lighter than the proton by roughly three orders of magnitude.
Step-by-Step Solution:
Verification / Alternative check:
Tables of fundamental constants list m_p/m_e ≈ 1836.152673, confirming the common approximation 1/1836 for m_e/m_p.
Why Other Options Are Wrong:
equal, infinite, about half, 1836 times: All contradict well-established mass ratios from experiment.
Common Pitfalls:
Mixing up which particle is heavier; misplacing decimal exponents when estimating the ratio.
Final Answer:
1/1836 of the proton mass
Discussion & Comments