A sphere with a diameter 1 meter has a mass of 120 kg. What is the mass, in kg, of a sphere of the same kind of material that has a diameter of 2 meters?

Question

anonymous · Answer

same material means that your density is constant. density = m/V so calculate the density of the 1m-diameter sphere. Then use that to find the mass of the other sphere

anonymous · Answer

i dont get it

anonymous · Answer

okay 
1. calculate the density of the first sphere. density=mass/volume and volume of the sphere is 4/3(pi)r^3 
2. then use that density to find the mass of the second sphere. since they are made of the same material, the two spheres have the same density.

anonymous · Answer

But it's not asking for the density though. The answer choices are 480, 560, 640, 960, and 1080. Or am i misreading the question.

anonymous · Answer

you have to use the density to find the mass

anonymous · Answer

then your answer should be 960

anonymous · Answer

Oooh! i get it now thank you!