48.6k views
1 vote
A particular planet has a moment of inertia of 8.26 × 1036 kg⋅m2 and a mass of 6.54 × 1022 kg. Based on these values, what is the planet's radius? Hint: Because planets are the shape of a sphere, the moment of inertia is I = (2/5)mr2.

7.12 × 106 m
1.78 × 107 m
5.05 × 1013 m
3.16 × 1014

User Bill Gary
by
8.1k points

2 Answers

6 votes

Answer:

1.78 x 10^7 m

Step-by-step explanation:

User Adam Jones
by
8.2k points
5 votes

Answer: Correct answer is B = 1.776933×
10^(7)

Explanation:

Given :

Moment of inertia I = 8.26×
10^(36) kg
m^(2)

Mass of planet m = 6.54×
10^(22) kg

Also, Planet is solid sphere so that, Moment of inertia is I =
(2)/(5) m
R^(2) =0.4m
R^(2)

Where R is radius of planet

Putting into calculation

We get,

I =
(2)/(5) m
R^(2)

8.26×
10^(36) = 0.4×6.54×
10^(22)×
R^(2)

8.26×
10^(14) = 2.616
R^(2)

3.15749235×
10^(14) =
R^(2)

R = 1.776933×
10^(7)

Thus, Correct answer is B = 1.776933×
10^(7)

User Jonatan Goebel
by
9.1k points