The correct answer is (A) 8.3mm.
The total displacement will be the vector sum of the two displacements given in the question.
let the displacement to the south represent vector A = 5mm in magnitude directed toward south.
let the displacement to the south-west represent vector B = 4mm in magnitude directed toward south-west.
The angle between vector A and vector B is 45°, the angle between south and south-west.
SO the resultant
R = vectro A + vector B
[tex]R=\sqrt{A^{2}+B^{2}+2ABcos(45) } \\\\R=\sqrt{25+16+40*\frac{1}{\sqrt{2} } } \\\\R=8.3mm[/tex]
The ant's displacement is 8.3 mm in magnitude.
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