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Grade upto college level General Physics

Two straight lines L1 and L2 cross each other at point P . The line L1 is moving at a speed v1 perpendicular to itself and line L2 is moving at speed v2 in the similar fashion. What will be the speed of point P?

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

Profile image of Deepak Patra
12 Years agoGrade upto college level
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1 Answer

Profile image of Saurabh Koranglekar
6 Years ago
Let S be the point on L1 vertically below P. From ∆ONQ, sinθ=v2/OQ. From ∆QSP, tanθ=v1/QS.

OS=OQ+QS

=v2/sinθ+v1/tanθ

=(v2+v1cosθ)/sinθ.

OP^2=OS^2+SP^2

=(v2+v1cosθ)^2/(sinθ)^2+v1^2

=(v2^2+2v1v2cosθ+v1^2.(cosθ)^2

+v1^2.(sinθ)^2)/(sinθ)^2

=(v2^2+2v1v2cosθ+v1^2)/(sinθ)^2.

The speed of point P is

OP=√(v2^2±2v1v2cosθ+v1^2)/sinθ.