A player kicks a soccer ball from ground level and sends it flying at an angle of 30 degrees at a speed of 26 m/s. What is the maximum height attained by the ball? Round to the nearest tenth of a meter.

Respuesta :

By definition, the height is given by:
 [tex]h (t) = (1/2) * (a) * (t ^ 2) + v0 * t + h0 [/tex]
 Where,
 a: acceleration
 v0: initial speed
 h0: initial height.
 The initial velocity in its vertical component is:
 [tex]v0 = 26 * sine (36) v0 = 15.3 m / s[/tex]
 The initial height is:
 [tex]h0 = 0 m[/tex] (the ball is on the ground)
 The acceleration is:
 [tex]a = -9.8 m / s ^ 2[/tex] (acceleration of gravity)
 Substituting values:
 [tex]h (t) = (1/2) * (- 10) * (t ^ 2) + 15.3 * t + 0 [/tex]
 Rewriting:
 [tex]h (t) = -4.9 * t ^ 2 + 15.3 * t [/tex]
 The time in which the maximum height occurs is obtained by deriving:
 [tex] h '(t) = -9.8 * t + 15.3 [/tex] We set zero and let's time:
 [tex]-9.8 * t + 15.3 = 0 t = 15.3 / 9.8 t = 1.56[/tex]
 We evaluate the time obtained in the equation of the height, to obtain the maximum height:
 [tex]h (1.56) = -4.9 * (1.56) ^ 2 + 15.3 * (1.56) h (1.56) = 11.9 m[/tex]
 Answer:
 
The maximum height attained by the ball is:
 
h (1.56) = 11.9 m