a man walking with a speed of v=2m/s constant in magnitude and direction passes under a lantern hanging at a - Physics - Motion In A Plane

Question

a man walking with a speed of v=2m/s constant in magnitude and
direction passes under a lantern hanging at a height p above the
ground find the velocity in m/s with the edge of the shadow of the
mans head moves over the ground , if his height is h given that p=
3h

Jyoti Pant · Accepted Answer

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"https://s3mn%20mnimgs%20com/img/shared/ck-files/ck_55ae2d1f17dbd%20png"
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Suppose s and S are the distances covered in a time interval 't' from the point O by the man and the edge of the shodow of the man's head respectively
From the figure, we have two similar triangles ABD and ACO
And DBAD=OCAOOr sH-h=SHBut we know that,s=vtSo,  vtH-h=SHNow, S/t=Speed of the shadow of the man's head,ThenV=HvH-hor V=pvp-hAccording to question,p=3hso,V=3hv3h-h=3hv2h=32v

a man walking with a speed of v=2m/s constant in magnitude and direction passes under a lantern hanging at a height p above the ground .find the velocity in m/s with the edge of the shadow of the mans head moves over the ground , if his height is h given that p= 3h