Question

A boat is moving with velocity $(3\hat{i}+4\hat{j})$ with respect to the ground. The water in the river is moving with a velocity $-3\hat{i}-4\hat{j}$ with respect to ground. The relative velocity of the boat with respect to water is

• A. $8\hat{j}$
• B. $6\hat{i}+8\hat{j}$
• C. $6\hat{i}+9\hat{j}$
• D. zero

Answer 1

The correct option is B $6\hat{i}+8\hat{j}$

Relative velocity of boat w.r.t. water
$=(3\hat{i}+4\hat{j})-(-3\hat{i}-4\hat{j})=6\hat{i}+8\hat{j}$
Option (b) is correct.