MCQ
A charged object is launched inside a time varying electric field. Its motion is recorded by a video camera on a video tape. When it is at a certain moment $A$ , its position vector $\vec r$, velocity $\vec v$ and acceleration $\vec a$ are measured. A student watches the video at a later time but mistakenly plays the tape in the reverse direction. What is the position, velocity, and acceleration of the object, at moment $A$ observed by the student respectively?
- A$\vec r,\vec v,\vec a$
- B$- \vec r, -\vec v, -\vec a$
- ✓$\vec r,- \vec v,\vec a$
- D$\vec r,\vec v,- \vec a$
