How to calculate the Euler class of the normal bundle of the sphere

Question

Let $S^n$ be the $n-$sphere, then $S^{n-1}$ is naturally a submanifold of $S^n$. So we can consider its normal bundle. How to calculate the Euler class of this normal bundle?

Answer 1

The Euler class vanishes if the bundle has a nowhere vanishing section. Can you find such a section for the normal bundle? You can either give an example of such a section or use the fact that $S^{n-1}$ is an orientable submanifold of $S^n$. An alternative way is to simply determine the cohomology class in which the Euler class lives in (for $n\neq 2$).