A projectile is launched at an angle α with the horizontal with a velocity 20 m s - 1 . After 10 s , its inclination with horizontal is β . The value of tan β will be : g = 10 m s - 2 .

Step-by-step solution

Component of velocity in horizontal direction, v x = 20 cos α = v 2 cos β Component of velocity in vertical direction, v y = 20 sin α - g × 10 = v 2 sin β ⇒ tan β = 20 sin α - 100 20 cos α ⇒ tan β = tan α - 5 cos α ⇒ tan β = tan α - 5 sec α