Question
Class ManagementHelp Bonus Homework 3 Begin Date: 9/13/2017 2:30:00 PM-Due Date: 9/22/2017 11:59:00 PM End Date: 9/23/2017 4:00:00 AM 15 m/s at a 196) Problem 6: A soccer ball is kicked from ground level across a level soccer field with initial velocity vector v 35° above horizontal. The soccer ball feels wind resistance which causes it to slow horizontally with constant acceleration magnitude a,-0.54 m/s2, while leaving its vertical motion unchanged. Assume any other air resistance is negligible. Choose the positive direction of r from initial point towards final point of flight. Use a Cartesian coordinate system with the origin at the ball's initial position. D 50% Part (a) The ball travels through the air until it returns to the soccer field. Calculate the ball's time of flight, trin seconds. Grade Su Deductions Potential cosO cotan asin acos0 atan0 acotansinh0 coshO n cotanhO 4 5 6 1 2 3 Submissions Attempts ren 596 per atte detailed vie Submit Hint give up Hints:-5% deduction per hint. Hints remaining: Feedback: 2 deduction per feedback. à 50% Part (b) Calculate the horizontal distance, xmar in meters, the ball travels before it returns to the soccer field.
Explanation / Answer
here,
initial speed , u = 15 m/s
theta = 35 degree
a)
let the time of fight be t
t = 2 * u * sin(theta)/g
t = 2 * 15 * sin(35)/9.81 s
t = 1.75 s
the time of flight is 1.75 s
b)
ax = - 0.54 m/s^2
the horizontal distance , x = u * cos(theta) * t + 0.5 * ax * t^2
x = 15 * cos(35) * 1.75 - 0.5 * 0.54 * 1.75^2
x = 20.7 m