JEE Main202628 January 2026Evening ShiftPhysicsRotational MotionActual
When the position vector r =x i +y j +z k changes sign as - r , which one of the following vector will not flip under sign change ?
Options
- AAngular momentum
- BVelocity
- CAcceleration
- DLinear momentum
Correct answer
A. Angular momentum
Step-by-step solution
The transformation r - r is known as a parity transformation (inversion through the origin). Vectors that change sign under parity are called polar vectors, while those that do not change sign are called axial vectors (or pseudovectors). Velocity is defined as v = d r dt . Since r - r , we have v - v . Acceleration is defined as a = d v dt . Since v - v , we have a - a . Linear momentum is defined as p = m v . Since v - v , we have p - p . Angular momentum is defined as L = r p . Under the transformation r - r and