How to compare stability of following two alkenes How to find which alkene is more stable ?. As same number of hydrogens are added across the double bond so I am not able to use the fact that more substituted alkene is more stable.

I was initially thinking in terms of steric effect (Repulsion Between the two methyl groups) which led me to believe the second alkene should be less stable but in answer given the second alkene is shown more stable .

Can somebody explain on what basis this result is deduced. Any help is appreciated.
The second alkene is more stable since it is symmetric. Achiral compounds are always more stable than chiral compounds due to the Gauche Effect. The explanation for why the Gauche Effect takes place is here.