Football Player Kicking Ball: Find Clearance of Uprights

  • Thread starter Thread starter hackett5
  • Start date Start date
  • Tags Tags
    Ball
AI Thread Summary
A football player kicks a ball at 20 m/s and an angle of 53 degrees towards uprights 36 meters away and 3.05 meters high. The calculations show the ball travels a horizontal distance of 39.23 meters and reaches a maximum height of 13.02 meters. To determine if the ball clears the uprights, the time it takes to reach 36 meters must be calculated, and this time should be used to find the corresponding height of the ball. The discussion emphasizes the need to apply the projectile motion equations to assess the ball's clearance. Ultimately, the player needs to evaluate the height of the ball at the 36-meter mark to conclude if it clears the uprights.
hackett5
Messages
9
Reaction score
0

Homework Statement



A football player has to kick a ball through the uprights that are 36m away and 3.05 high. He kicks the ball at 20m/s and at an angle of 53 degrees. By how much does the ball clear or fall short of the goal?

Homework Equations


Horizontal Range= vi2 sin 2\Theta/ g

Height = vi2sin2\Theta/2g

The Attempt at a Solution



Using the formulas for range and hieght, I found that the ball traveled a total of 39.23m and reached a maximum height of 13.02. The ball traveled far enough, but how do I find how high the ball was at 36m to see if there was enough height?
 
Physics news on Phys.org
Hint: calculate the time at which the ball was at 36 m, and then plug that time into the equation that determines the height of the ball.
 
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top