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Question
A particle of mass 5 units is moving with a uniform speed of v = `3sqrt 2` units in the XOY plane along the line y = x + 4. Find the magnitude of angular momentum
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Solution
Given,
Mass = 5 units
Speed = v = `3sqrt 2` units
Y = X + 4
Angular momentum = L = m`(overliner xx overlinev)`
= `m(Xhati + yhatj) xx (vhati + vhatj) = m[xvhatk - vyhatk] = m[xvhatk - v(x + 4)hatk]`
L = `-mvhatk = -4 xx 5 xx 3sqrt2hatk = -60sqrt2hatk`
L = `60sqrt2` units.
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