Q. 295.0( 7 Votes )
A body moves 6 m north, 8 m east and 10m vertically upwards. What is its resultant displacement from the initial position?
North be positive x-axis
East be positive y-axis
Upwards be positive z-axis
Let be the displacements along north, east and upward direction respectively.
So, net displacement =
Magnitude of displacement:
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Motion in two dimensions, in a plane can be studied by expressing position, velocity and acceleration as vectors in Cartesian co-ordinates A = Axî + Ayĵ where î and ĵ are unit vector along x and y directions, respectively and Ax and Ay are corresponding components of (Fig. 4.9). Motion can also be studied by expressing vectors in circular polar co-ordinates as A = Ar + Aɵ where = = cosθ î + sin θ ĵ and = − sin θ î +cos θ ĵ are unit vectors along direction in which ‘r’ and ‘θ ’ are increasing.
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