Question

An old man and a boy are walking towards each other and a bird is flying over them as shown in the figure. Find the velocity of bird as seen by the boy.

• A. $12\hat{j}$
• B. $16\hat{j}$
• C. $-12\hat{j}$
• D. $-16\hat{j}$

Answer 1

The correct option is A $12\hat{j}$

From the figure,

Velocity of Boy with respect to ground is, $\overrightarrow{v_B}=16\hat{i}$

Velocity of Bird with respect to ground is, $\overrightarrow{v_b}=16\hat{i}+12\hat{j}$

So, velocity of bird with respect to boy is, $\overrightarrow{v_b}-\overrightarrow{v_B}=16\hat{i}+12\hat{j}-16\hat{i}=12\hat{j}$

So option A is correct.