Question

The ceiling of a hall is 40m high.For maximum horizontal distance, the angle at which the ball may be thrown with a speed 56m/s without hitting the ceiling is?

Answer 1

V² sin² Ф -  2 g H = 0²    =>  V² sin² Ф = 2 g H  => 56 * 56 sin² Ф = 2 * 9.8 * 40
         Sin² Ф = 1/4  => sin Ф = 1/2  =>  30 degrees

Maximum height = H        Range = R    angle of projection = Ф
 H / R  =  (1/4 ) tan Ф
 H = 40 m 
   tan Ф = 1/√3
Maximum range = R = 160 √3 m at this angle 30 deg

Answer 2

Explanation:

• refer to the attachment givens above hope it will help you