Bonds in Pentane vs 2-2 dimethylbutane?

[Angeline 3E]

In lecture, why is pentane stronger than 2-2 dimethylbutane? I know it's because of the shape ... but 2-2 dimethylbutane looks like the atoms would be closer together based on the structure? Can I get a clarification ?

[Midori Hupfeld 3D]

For pentane versus dimethylpropane, they have the same number of electrons, but the shape is what makes it closer. Rod-shaped molecules have their 2 dipoles closer to each other if you look at the drawing Dr. Lavelle showed in class, while the spherical shaped one has one dipole-dipole interaction that is close, but the other dipoles are far apart. I think this is what it means by shape contributes to the strength of the bonds.

[karinaseth_1A]

Rod shaped molecules have more potential points of interaction in the electron clouds when you lay them flat against each other the long way. Spherical molecules, however, have limited points of interaction because they can only experience dipoles on one point on the surface of their electron cloud.