FIITJCC RANKERS STUDY MATERIAL . IIT - JEE, 2002 PRACTICE FULL TEST -1 PHYSICS SOLUTION Velocity of stream at hole v0 = 7 2 g(H - x) horizontally. Let stream strikes the incline after time t at P, at that moment. Vx = v0 Vy = - gt Stream at the point of strike, makes an angle of 60° with horizontal downward. => =>
v
tan (-60°) x
gt = Vo V3
. . . (1)
PQ = ON = OM - MN = x - h = x - — gt2 2 For incline PQ = OQ tan 30° = PN tan 30° = v 0 1 tan 30° =>
x - - gt2 = v 0 1 tan 30°
2 2
g
g x
From (1) and (2)
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_ 5 v| 2 g 5 50 0 x = _ H = — = 8.33 m. 6 6
x=-2(H-x)=> Velocity of source after time t g
}V3v 0
=Vo
2g The frequency of sound changes due to the Doppler effect ,-M v s + v 0 cos60° 1On0 n' = n 0
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vs = 5v0. FIITJCC, ICES H o r n ' , (Opp. Vijay Mandal Enclave), Sarvapriya Vibar, New Delhi - 16. PA: 6865182, 6854102. Fax: 6J1J942