A place kicker must kick a football from a point 36.4 m from a goal. WEBASSIGN

[Eric]

PHYSICS??!!!? A place kicker must kick a football from a point 36.4 m from a goal. As a result of the kick, the ball must clear the crossbar, which is 3.05 m high. When kicked the ball leaves the ground with a speed of 19.5 m/s at an angle of 53° to the horizontal.

By how much does the ball clear the horizontal of the crossbar?

 

[garypopkin]

The horizontal component of the velocity at take-off is 19.5 * cos(53). The vertical component is 19.5 * sin(53).

The time to travel to the goal post is

36.4 / (19.5*cos(53)) = 3.1 seconds

The height of the ball above the ground after 3.1 seconds is given by

h = 19.5 * sin(53) * 3.1 - (1/2) * g * 3.1^2

 

[Stephen A. Smith]

time taken to travel 36.4 m = 3.1s

d = vi t -1/2g t^2 = 1.16 m.

It does not clear the horizontal of the crossbar. It is 3.05-1.16 = 1.89 m under the crossbar

 

[Stephen A. Smith]

time taken to travel 36.4 m = 3.1s

d = vi t -1/2g t^2 = 1.16 m.

It does not clear the horizontal of the crossbar. It is 3.05-1.16 = 1.89 m under the crossbar

 

[Stephen A. Smith]

time taken to travel 36.4 m = 3.1s

d = vi t -1/2g t^2 = 1.16 m.

It does not clear the horizontal of the crossbar. It is 3.05-1.16 = 1.89 m under the crossbar

 

[Stephen A. Smith]

time taken to travel 36.4 m = 3.1s

d = vi t -1/2g t^2 = 1.16 m.

It does not clear the horizontal of the crossbar. It is 3.05-1.16 = 1.89 m under the crossbar