Question

From the window of a building, a ball is tossed from a height y0 above the ground with an initial velocity of 8.40 m/s and angle of 25.0° below the horizontal. It strikes the ground 6.00 s later.

(a) If the base of the building is taken to be the origin of the coordinates, with upward the positive y-direction, what are the initial coordinates of the ball? (Use the following as necessary: y0. Assume SI units. Do not substitute numerical values; use variables only.) xi = Correct: Your answer is correct. yi = Correct: Your answer is correct.

(b) With the positive x-direction chosen to be out the window, find the x- and y-components of the initial velocity. vi, x = 7.61 Correct: Your answer is correct. m/s vi, y = -3.55 Correct: Your answer is correct. m/s

(c) Find the equations for the x- and y-components of the position as functions of time. (Use the following as necessary: y0 and t. Assume SI units.) x = Correct: Your answer is correct. m y = Correct: Your answer is correct. m

(d) How far horizontally from the base of the building does the ball strike the ground? 45.68 Correct: Your answer is correct. m

(e) Find the height from which the ball was thrown. 197.88 Correct: Your answer is correct. m

(f) How long does it take the ball to reach a point 10.0 m below the level of launching? 1.4 Incorrect: Your answer is incorrect.

Can you help me with (f)?

Answer 1

Coyo) (a) Initial Cocodinats of ball are (b) initial a velocity = V. Cosas = 8.4Cosas = 7.6 m/s. initial y velocity Vosinas = 8.usinas = 3.55(-ve, dieaction (C) X(t) = X. + Vell)t + (a) W+ 1670, Vo(x) = 7.6mls and acc. in the x direction there is no so, Joc (t) = 7.6 € yt) = yo + VOCH) – bagt yC) = yo - 3586 Igth (d) we are told the total time is 60, so we know that x borition at t = 6s is. of travel the x (6) = 7.6+6 = us. 6m.

ce we find yo by solving the equation y(6) - yo - 3.556) - 4 (98)66)* Since we know the ball hits the ground Cy=o) when t= 65. So we have yo - 21.4 176.4 = 0 yo = 197.8m 44) - 10. 80 y(t) = Ye - 3.55 t - 19.8 t² 103 197.8 -3.854 - 1984? 4.9+'+ 3,55 t - 187.8 -0. te – 3.55 + 13.5S-u (.) (-187.8) gxu.a so t = 5.83 sec By solving above equation.