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Karnataka Board PUCPUC Science Class 11

A Mosquito Net Over a 7 Ft × 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 - Physics

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Question

A mosquito net over a 7 ft × 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, it width as the Y axis, and vertically up as the Z-axis, write the components of the displacement vector.

Answer in Brief
Sum
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Solution

Displacement vector of the mosquito,

\[\vec{r} = 7 \hat {i} + 4 \hat {i} + 3 \hat {k}\]
(a) Magnitude of displacement
\[= \sqrt{7^2 + 4^2 + 3^2}\]
\[= \sqrt{74} \text { ft }\]
(b) The components of the displacement vector are 7 ft, 4 ft and 3 ft along the X, Y and Z-axes, respectively.
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Chapter 2: Physics and Mathematics - Exercise [Page 29]

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HC Verma Concepts of Physics Vol. 1 [English] Class 11 and 12
Chapter 2 Physics and Mathematics
Exercise | Q 9 | Page 29

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