Planet Surface Temperature Order
The surface temperature of planets generally increases with proximity to the Sun. However, atmospheric composition plays a crucial role, as seen with Venus's extreme heat due to a runaway greenhouse effect. Mercury, despite being closer to the Sun than Venus, has lower average temperatures due to its lack of atmosphere.
Planet Temperatures
| Planet | Approximate Average Surface Temperature |
| Neptune | $ \approx -214^{\circ} \text{C} $ |
| Earth | $ \approx 15^{\circ} \text{C} $ |
| Mercury | $ \approx 167^{\circ} \text{C} $ (Average) |
| Venus | $ \approx 462^{\circ} \text{C} $ |
Correct Temperature Sequence
Based on the approximate average surface temperatures, the planets listed in order of increasing temperature are:
- Neptune ($ \approx -214^{\circ} \text{C} $)
- Earth ($ \approx 15^{\circ} \text{C} $)
- Mercury ($ \approx 167^{\circ} \text{C} $)
- Venus ($ \approx 462^{\circ} \text{C} $)
Therefore, the correct sequence is Neptune, Earth, Mercury, Venus.
Important Questions from Planetary Bodies
- Atmosphere of planet Mars is almost entirely made up of $\text{CO}_2$. But the surface temperature of Mars is less than that of the Earth because:
- Consider two planets A and B with radii $2r$ and $r$, respectively. Let their distances from the Sun be $d$ and $2d$, respectively. The solar constants for A ($F_{\text{SA}}$) and B ($F_{\text{SB}}$) are related by
- Consider two planets 'A' and 'B' with the following characteristics. The relationship between $T_1$ and $T_2$ is
Distance from the Sun Radius of the planet Incident Solar flux density Equivalent temperature Planet A $d_1$ $r_1$ $F_1$ $T_1$ Planet B $d_2 = 4d_1$ $r_2 = 2r_1$ $F_2$ $T_2$ - Venus is closer to the Sun than Earth, and therefore solar energy incident on Venus is higher than that on Earth. However, the effective radiating temperature of Venus is lower than that of the Earth, because
A planet of radius $r$ has a core of radius $r_c$ and a mantle. It has no crust. Its mean density is $\rho$ and the density of its core is $\rho_c$. What is the density of the mantle?
