Assuming the sun to have a spherical outer surface of radius r

⇦

⇨

Assuming the sun to have a spherical outer surface of radius r, radiating like a black body at temperature t⁰C, the power received by a unit surface, (normal to the inicident rays) at a distance R from the centre of the sun is

Options

(a) r²σ (t + 273)⁴ / 4πR²
(b) 16 π²r² σt⁴ / R²
(c) r²σ (t + 273)⁴ / R²
(d) 4 πr² σt⁴ / R²

Correct Answer:

r²σ (t + 273)⁴ / R²

Explanation:

Power radiated by the sun at tC
= σ (t + 273)⁴ 4πr²
Power received by a unit surface
σ (t + 273)⁴ 4πr² / 4πR²
r²σ (t + 273)⁴ / R²

Related Questions:

1. In vacuum, to travel distance d, light takes time t and in medium to travel distance
2. Light of frequency 8×10¹⁵ Hz is incident on a substance of photoelectric work
3. The velocity of electromagnetic radiation in a medium of permittivity ε₀
4. If r be the distance of a point on the axis of a magnetic dipole from its centre
5. The periodic waves of intensities I₁ and I₂ pass through a region at the same time

Topics: Properties of Bulk Matter (130)
Subject: Physics (2479)

---

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

---

Share this page with your friends