Question

A particle is projected with velocity 50 metre per second at an angle 60 degree with the horizontal from the ground the time after which its velocity will make an angle 45 degree with the horizontal

Answer 1

Answer:

Step-by-step explanation:

Here the angle of projection being 60°,the velocity being 100m/s gives the components of velocity as vertical=100sin60°=50√3,

horizontal=100cos60°=50.Now throughout the time of flight the horizontal component remains same,so 50m/s.The vertical component varies under gravity. So at any time it becomes 50√3-g×t

=50√3–10t(assumption of g approximated 10m/s²) when the projectile’s position becomes 45° to horizontal=>(50√3–10t)/50=tan45°=1

=>50√3–10t=50

=>10t=50(√3–1)=50×0.732=36.6=>t=3.66s after being projected.