Since sun is faraway from the earth, the sun rays can be assumed parallel when they reach the earth surface.

Q. Heat rays reach the earth from the sun through

Q. The solar constant is the amount of heat energy received per second per unit area of a perfectly black surface placed at a mean distance of the Earth from the Sun, in the absence of Earths atmosphere, the surface being held perpendicular to the direction of Suns rays. Its value is $1388W/m^2$.If the solar constant for the earth is $s$. The surface temperature of the sun is $TK$, $D$ is the diameter of the Sun, $R$ is the mean distance of the Earth from the Sun. The sun subtends a small angle $\theta$ at the earth. Then correct options is/are :

Q. The light from the sun to reach the surface of the earth takes about _____.

Q. The light from the sun takes $500s$ to reach the earth. Assuming that the speed of light is $3,00,000km/s$, calculate the distance between the sun and the earth.

Q. Time taken by the light to reach the surface of the earth from the sun is _____ .