Question

A mosquito net over a 7 ft \times 4 ft bed is 3 ft high. The net has a hole at one corner of the bed through which a mosquito enters the net. It flies and sits at the diagonally opposite upper corner of the net.

(a) Find the magnitude of the displacement of the mosquito.

(b) Taking the hole as the origin, the length. of the bed as the X-axis, its width as the Y-axis, and vertically up as the Z-axis, write the components of the displacement vector.

Answer 1

Displacement vector

$\overrightarrow{r}=7\hat{i}+4\hat{i}+3\hat{k}$

(a) Magnitude of displacement

= $\sqrt{7^2+4^2+3^2}$

= $\sqrt{74}$ ft

(b) Components of the displacement vector are 7 ft, 4 ft and 3 ft.