Concepts Of Physics MCQ Edition [Volume 1]PhysicsRotational Mechanics
A particle travels with a constant velocity parallel to the X -axis. Its angular momentum relative to the origin
Options
- Acontinuously decreases
- Bis zero
- Ccontinuously increases
- Dremains constant
Correct answer
D. remains constant
Step-by-step solution
Let the particle move along a line parallel to the X -axis with a constant velocity v = v i . The position vector of the particle at any time t is r = x i + y j + z k . Since the particle moves parallel to the X -axis, its y and z coordinates remain constant. The angular momentum of the particle relative to the origin is given by L = r p , where p = m v is the linear momentum. L = (x i + y j + z k ) (mv i ) L = m v (x ( i i ) + y ( j i ) + z ( k i )) L = m v (0 - y k + z j ) L = m z v j - m y v k Since m , v , y ,