Question

ano
Example 2. A body travels 4 km towards North then he turn to his right and travels
4 km before coming to rest. Calculate (i) total distance travelled, (ii) total displacement
Solution :
4km
A
B.
4km
displacement
W
E
S​

Answer 1

Given :

A body travels 4 km towards North then covers 4 km to his right.

To Find :

Total distance travelled and total displacement.

Solution :

❖ Distance is defined as the actual length of path which is covered by the moving object.

- It is a scalar quantity having only magnitude.

- SI unit : m

Here in this question total distance travelled by the body will be the sum of two individual path lengths.

$\sf\dashrightarrow\:Distance=AB+BC$

$\sf\dashrightarrow\:Distance=4+4$

$\dashrightarrow\:\underline{\boxed{\bf{\orange{Distance=8\:km}}}}$

❖ Displacement is defined as the shortest distance between initial and final position of the entire journey.

- It is a vector quantity having both magnitude as well as direction.

- SI unit : m

- It can be positive, negative or zero.

$\sf\dashrightarrow\: Displacement\:(AC)=\sqrt{(AB)^2+(BC)^2}$

$\sf\dashrightarrow\: Displacement\:(AC)=\sqrt{4^2+4^2}$

$\sf\dashrightarrow\: Displacement\:(AC)=\sqrt{2(4)^2}$

$\sf\dashrightarrow\:\underline{\boxed{\bf{\gray{Displacement\:(AC)=4\sqrt2\:km\:[NE]}}}}$