Question

River is flowing with velocity 2i + 3 J and boat is moving with 4i + J with respect to the ground. Then the relative velocity of boat with respect to the river is

• A. $6i+2J$
• B. $2i-2j$
• C. $I+J$
• D. $4i-3j$

Answer 1

The correct option is B $2i-2j$

Given,

The velocity of river with respect to ground,

$v_{RG}=2\hat{i}+3\hat{j}$

The velocity of boat with respect to ground,

$v_{BG}=4\hat{i}+\hat{j}$

The relative velocity of boat with respect to the river water,

$v_{BR}=v_{BG}-v_{RG}$

$v_{BR}=(4\hat{i}+\hat{j})-(2\hat{i}+3\hat{j})$

$v_{BR}=2\hat{i}-2\hat{j}$

The correct option is B.