Question

If Sun is emitting energy 1.5 × 10³ cal / s from each of its cm² surface. If Stefan’s constant is 5.7 × 10^-8 J/s¹ m² K⁴ then estimate the surface temperature of the Sun.

Answer 1

Given; E = 1.5 × 10³ cal s^-1 cm^-2
= 1.5 × 10³ × 4.2 × 10⁴ J.s^-1 m^-2
= 6.30 × 10⁷ J.s^-1 m^-2
σ = 5.7 × 10^-8 J.s^-1.m^-2.K^-4