A Boy has a ball and throws it straight up into the air with an initial velocity of 6 m/s. Calculate the maximum height of the ball and the time the ball is in the air.

Respuesta :

Answer:

i. 1.84 m

ii. The ball's time in the air is 1.23s.

Explanation:

The ball moves upward (against the gravitational pull) with an initial velocity of 6 m/s.

I. Applying the third equation of free fall, the maximum height is;

[tex]V^{2}[/tex] = [tex]U^{2}[/tex] - 2gs

where the variables have there usual meaning.

[tex]V^{2}[/tex] = 0 m/s, [tex]U^{2}[/tex] = 6 m/s, g = 9.8 m/[tex]s^{2}[/tex].

0 = [tex]6^{2}[/tex] - 2 x 9.8 x s

0 = 36 - 19.6s

⇒ 19.6s = 36

s = [tex]\frac{36}{19.6}[/tex]

 = 1.8367

 = 1.84 m

The maximum height of the ball is 1.84 m.

II. The time the ball was in air can be determined by,

time of flight, T = [tex]\frac{2USin A}{g}[/tex]

where U is the initial velocity of the ball, A is the angle of projection and g is the acceleration due to gravity.

U = 6 m/s, A = [tex]90^{o}[/tex] (since the ball is thrown vertically upward), and g = 9.8 m/[tex]s^{2}[/tex].

T = [tex]\frac{2 *6 Sin90^{o} }{9.8}[/tex]

  = [tex]\frac{12}{9.8}[/tex]

  = 1.2245

T = 1.23s

The ball's time in the air is 1.23s.