Question

Objects A and B are at the origin. If object A moves to `(-3 ,-5 )` and object B moves to `(7 ,9 )` over `3 s`, what is the relative velocity of object B from the perspective of object A? Assume that all units are denominated in meters.

Answer 1

The relative velocity is `= <10/3, 14/3> ms^-1`

Explanation:

The absolute velocity of `A` is `v_A=1/3 <-3,-5> = <-1,- 5/3> ms^-1`

The absolute velocity of `B` is `v_B=1/3 <7,9> = <7/3, 3> ms^-1`

The relative velocity of `B` with respect to `A` is

`v_(B//A)=v_B-v_A`

`=<7/3, 3> - <-1, -5/3>`

`= <7/3+1, 3 +5/3>`

`= <10/3, 14/3> ms^-1`