Pluto's radius is just under 1.2 megameters (Mm). What is its surface area? (Use the π symbol in your answer)

Question

Pluto's radius is just under 1.2 megameters (Mm). What is its surface area? (Use the π symbol in your answer)

Answer 1

4 π r^2

 

4 * 3,1416 * 1.2Mm*1.2Mm

Answer 2

     One megameter is equal to one million meters or 1000 Km. Therefore, 1.2 megameters = 1,200,000 meters because you need to move the decimal point over 6 places for the 6 zeros in one million. Also, Pluto's gravity causes it to be in the shape of a sphere, so you can use the formula for finding the area of a sphere.  Recall that a sphere is the shape of a ball. 

 

 Since they want the answer with the π (pi) symbol, don't convert it to any value.          

A= 4 π r^{2                                                                                                                                                                                              6}

  = 4 * π* (1,200,000 m)^{2       The one million, 200 thousand Mm can also be written in scientific notation, such as 1.2* 10  .}  

                   6          6                      12              12

  ^{Also, (1.2*10  )(1.2*10  )= 1.2*1.2 * 10     = 1.44* 10         squared meters}

^{Then multiply by 4 and then just keep the π (pi), and you are done.     Remember that the answer is in square meters because it is area.}

     Since this is a planet, it might be easier and more logical to convert to Km at the beginning of the problem, but that would cause you to rework it.  Your answer would then be in square Km.

Answer 3

If we assume that Pluto is a sphere, then we can use the formula for the surface area of a sphere, which is:

 

A = 4πr², where r = radius