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Grade 11General Physics

one second after projection, a stone moves at an angle 45° with horizontal. two second after projection, it moves horizontally. its angle of projection is tan^-1 (2). Then what is its initial velocity.

Profile image of MANOJ SAINI
9 Years agoGrade 11
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1 Answer

Profile image of Vikas TU
9 Years ago
General eqn. at time gt in x and y direction respectively are = >
Vx = ucos(theta)
Vy = usin(theta) – gt
 
At t = 2 s, Vy = 0
usin(theta) – 2g = 0
u = 2g/sin(theta) = > 2g/(2/root5) { given theta = tan^-1 (2)}
u = g*root(5) m/s.