What is the magnetic-field energy in a given volume with B = 3.50T?

[Jack_M]

Homework Statement

What is the magnetic-field energy in a 10.0cm³ volume of space where B = 3.50T?

Homework Equations

u = B²/2μ₀

The Attempt at a Solution

Using the equation I got an answer of 4.87*10⁵ J/m³ which is incorrect

 

[phyzguy]

It doesn't ask for the energy density, which is what you gave. It asks for the energy, so your final answer should be in Joules, not Joules/m^3.

 

[Jack_M]

It doesn't ask for the energy density, which is what you gave. It asks for the energy, so your final answer should be in Joules, not Joules/m^3.

Should an answer using that formula along with those units be correct, though? I only have 2 more submissions available.

 

[phyzguy]

Should an answer using that formula along with those units be correct, though? I only have 2 more submissions available.

Yes, you're on the right track. You have calculated the energy density almost correctly. I got 4.87*10⁶ J/m3, so one of us made a mistake. Then how do you go from energy density to energy?

 

[Jack_M]

Oh I see now. I should multiply by the volume of the space correct?

 

[phyzguy]

Yes.