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A kicker attempts a field goal in a football game; note that a football is kicked off the ground during a field goal attempt. The kicker attempts his kick 32.0 m from the base of the goalposts, whose crossbar is 3.00 m above the ground. If the kick has an initial velocity of 20.0 m/s at an angle of 37° above the ground, will the football pass over the crossbar and be a field goal? Assume that the football is kicked straight on (i.e. directly between the goalposts), so it does not veer left or right while in flight.

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Answer:

the football will pass over the crossbar and be a field goal.

Step-by-step explanation:

To determine whether the football will pass over the crossbar and be a field goal, you can use the equations of projectile motion. The key parameters are the initial velocity, angle, distance to the goalposts, and the height of the crossbar.

The horizontal distance traveled by the football (range) can be calculated using the following formula:

Range (R) = (v^2 * sin(2θ)) / g

Where:

- v is the initial velocity (20.0 m/s).

- θ is the angle above the ground (37°), which should be converted to radians.

- g is the acceleration due to gravity (approximately 9.81 m/s²).

First, convert the angle to radians:

θ = 37° * (π/180) ≈ 0.645 radians

Now, plug in the values and calculate the range:

R = (20.0 m/s)^2 * sin(2 * 0.645) / 9.81 m/s²

R ≈ 68.6 meters

The goalposts are 32.0 meters away from the kicker. To be a successful field goal, the football must travel a horizontal distance of 32.0 meters and reach a height of at least 3.00 meters (the height of the crossbar). From the calculated range, the football clearly travels far enough horizontally, but you also need to find the maximum height it reaches to see if it clears the crossbar.

The formula for the maximum height (H) is:

H = (v^2 * (sin(θ))^2) / (2 * g)

Plug in the values:

H = (20.0 m/s)^2 * (sin(0.645))^2 / (2 * 9.81 m/s²)

H ≈ 7.75 meters

The football reaches a maximum height of approximately 7.75 meters, which is well above the 3.00-meter crossbar. Therefore, the football will pass over the crossbar and be a field goal.

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