MCQ
A Body moves $6\, m$ north. $8 \,m$ east and $10\;m$ vertically upwards, what is its resultant displacement from initial position
- ✓$10\sqrt 2 m$
- B$10m$
- C$\frac{{10}}{{\sqrt 2 }}\,m$
- D$10 \times 2\,m$
✓
Answer
Correct option: A.
$10\sqrt 2 m$
a
(a) $\vec r = x\hat i + y\hat j + z\hat k$
(a) $\vec r = x\hat i + y\hat j + z\hat k$
$\therefore r = \sqrt {{x^2} + {y^2} + {z^2}} $
$r = \sqrt {{6^2} + {8^2} + {{10}^2}} = 10\sqrt 2 \;m$
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