Question

determine the average density of the planet mars .given that its parameter = 6780 km ,and the acceleration due to gravity on this surface = 0.38 g​

Answer 1

Answer: 1.26 × 10⁶ kg/m³.

Explanation:

Let us assume that, the Mars is a perfect sphere.

Now we know,

1. g = GM/R²
2. M = d 4/3 πR³

[V (sphere) = 4/3 πR³.]

C = 2πr = 6780 km (Given)

=> r = 3390/π km

From (1), M = R²g/G and therefore, from (1) and (2):

d 4/3 π R³ = R²g/G

=> d 4/3 π R = g/G

=> 4/3·d = g/πRG

=> d = 3g/4πRG

=> d = 3(0.38)/(4 × π × 3390/π × 6.67 × 10^-11) kg/m³

=> d = 1.26 × 10⁶ kg/m³.

So, the average density of Mars is 1.26 × 10⁶ kg/m³.