Science
hardQ. No. 15171-what-is-the-total-radiation-pyrometer-based-on
What is the total radiation pyrometer based on?
Last Updated:
AWien's law
BNewton's cooling law
CSnell's law
DStefan's law
Correct Answer: Stefan's lawYour Answer: D
Explanation
The Total Radiation Pyrometer collects all radiation from a hot body to measure temperature. Option A is wrong — Wien's law relates peak wavelength to temperature and is used by Optical Pyrometers, not Total Radiation Pyrometers. Option B is wrong — Newton's cooling law describes rate of heat loss by convection and has no role in pyrometry. Option C is wrong — Snell's law is about refraction of light at boundaries and is unrelated to temperature measurement. Option D is CORRECT — Total Radiation Pyrometer is based on Stefan-Boltzmann law: E = σT⁴. It collects all wavelengths of radiation from the hot body and focuses them on a thermocouple or bolometer. By measuring total energy received, temperature is calculated using Stefan's law. This is slightly wider than Optical Pyrometer (800°C to 2700°C). Stefan constant σ = 5.67×10⁻⁸ W/m²K⁴.
Related Questions
View All15188-what-phenomenon-causes-a-pen-to-dry-out-and-how-does-putting-the-cap-on-prevent-itWhat phenomenon causes a pen to dry out and how does putting the...15187-why-do-biscuits-kept-in-a-refrigerator-without-a-cover-become-dry-and-crispyWhy do biscuits kept in a refrigerator without a cover become dry...15186-what-is-the-function-of-a-thermostat-in-a-refrigeratorWhat is the function of a thermostat in a refrigerator?
Test your Heat knowledge
Start Topic TestFAQ
Heat FAQs
Common questions and clear answers for this topic.
What is heat in physics?
Heat is a form of energy that transfers between objects or systems due to a temperature difference, moving from a hotter body to a cooler one until thermal equilibrium is reached.