Question

A truck travelling due to north at `20m s^(-1)` turns west and travels at the same speed. Find the change in its velocity.
A. `40m//s S-W`
B. `20 sqrt(2)m//s N-W`
C. `40 m//s S-W`
D. `20 sqrt(2)m//s S-W`

Answer 1

Correct Answer - D
From (figure)
`vec(v)_(1)= 20hat(j) and vec(v)_(2)= -20hat(i)`
`Deltavec(v)= vec(v)_(2)-vec(v)_(1)= -20(hat(i)+hat(j))`
`|Deltavec(v)|=20 sqrt(2)` and direction
`theta= tan^(-1)(1)= 45^(@)` i.e., S-W