To win the game, a placekicker must kick a football from a point 44 m (48.1184 yd) from the goal, and the ball must clear the crossbar, which is 3.05 m high. When kicked, the ball leaves the ground with a speed of 24 m/s at an angle of 31◦
from the horizontal.
The acceleration of gravity is 9.8 m/s^2.
By how much vertical distance does the ball clear the crossbar?
Answer in units of m.

Respuesta :

Answer:

The distance by the ball clear the crossbar is 1.15 m

Explanation:

Given that,

Distance = 44 m

Speed = 24 m/s

Angle = 31°

Height = 3.05 m

We need to calculate the horizontal velocity

Using formula of horizontal velocity

[tex]u_{x}=u\cos\theta[/tex]

Put the value into the formula

[tex]u_{x}=24\cos(31)[/tex]

[tex]u_{x}=20.5\ m/s[/tex]

We need to calculate the vertical velocity

Using formula of vertical velocity

[tex]u_{y}=u\sin\theta[/tex]

Put the value into the formula

[tex]u_{y}=24\sin(31)[/tex]

[tex]u_{y}=12.3\ m/s[/tex]

We need to calculate the time

Using formula of time

[tex]t=\dfrac{d}{u_{x}}[/tex]

Put the value into the formula

[tex]t=\dfrac{44}{20.5}[/tex]

[tex]t=2.1\ sec[/tex]

We need to calculate the vertical height

Using equation of motion

[tex]h=u_{y}t+\dfrac{1}{2}at^2[/tex]

Put the value into the formula

[tex]h=12.3\times2.1-\dfrac{1}{2}\times9.8\times(2.1)^2[/tex]

[tex]h=4.2\ m[/tex]

We need to calculate the distance by the ball clear the crossbar

Using formula for vertical distance

[tex]d=h-3.05[/tex]

Put the value of h

[tex]d=4.2-3.05[/tex]

[tex]d=1.15\ m[/tex]

Hence, The distance by the ball clear the crossbar is 1.15 m