A physics book is moved once around the perimeter of a table of dimensions 1 m by 3 m. if the book ends up its initial postion.what is the magnitude of its displacement? what is the distance traveled?
The displacement will be ZERO as it did not move from its initial position but distance covered will be equal to the peremeter, i.e.
2(1+3)m = 2(4)m = 8m
The dimension of the table = 1m by 3m. Assume the table a rectangular (or parallelogram rarely)
Therefore, the length of the perimeter of the table = 2(length+breadth)=2(1+3)=8meter
Therefore the distance travelled by the book by its travellin onc along the perimeter and coming back to the starting point = 8meter.
But the displacement of the book considering its directions is =3m along the length +1m along the width direction -3m along the length and -1m along the width = 0, as the book is is at the starting postion only after all its travel.