Chapter 3, Problem 52P

To determine

To find: Relative velocity of car 1 seen by 2 and relative velocity of car 2 to car 1.

Answer to Problem 52P

The velocity of car seen by 2 will be 65.19km/hr and for car 2 to car 1 it is -65.19km/hr.

Explanation of Solution

Given Data:

  $\begin{array}{l}\text{Velocity of car, }{V}_{1E}=35\text{ km/hr}\\ \text{Velocity of car, }{V}_{2E}=55\text{ km/hr}\end{array}$

Calculation:

The velocity triangle is drawn as:

  

Relative velocity of car 1 with respect to car 2

  $\begin{array}{l}{V}_{12}=35j-55i\\ \left({\overrightarrow{V}}_{12}\right)=\sqrt{{35}^2+{55}^2}\\ \left({\overrightarrow{V}}_{12}\right)=65.19\text{km/hr}\end{array}$

Relative velocity of car 2 with respect to car 1:

  $\begin{array}{l}{V}_{21}=55i-35j\\ V_{21}=-65.19\text{km/hr}\end{array}$

Where, negative sign indicates that the velocity is in opposite direction of the first case.