Question

  Solve for me this problems. Please solve 14, 15, 16. Thank you so much. all problems.

14) A large rock falls from the side of a cliff. It falls 8.5 m before striking a car driving at 95 km/hr. From the frame of reference of the car, what is the velocity and angle of impact? 15) A stunt rider needs to clear 24 m with her motorcycle using a launch ramp. The ramp is at an angle of 30 and the edge is 2.0 m high. What is the minimum velocity needed? 16) Golf. Your formulas from #11 above will be useful. a. What is the time of flight for a golf ball hit at a 32° angle at 55 m/s? b. What is the range if the ball is hit at a 60" angle and 41 m/s? The center of the green is 112 m away. Which club should you select: the 7-iron, which lofts the ball at 37 at 38 m/s; the 8-iron (41 at 36 m/s); or the 9-iron (46 at 33 m/s)? c.

Answer 1

Velocity of rock w.r.t ground V_r^2 = 2 gh = > V_r = squareroot 2 gh = squareroot 2 times 9.21 times 8.5 = 12.91 m/s Velocity of car w.r.t ground V_c = 95 km/h = 95 times 1000 m/3600 s = 26.39 m/s Velocity of rock with respect to car V^vector_r-c = V^vector_r - V^vector_c Vertical-bar V_r-c Vertical-bar = squareroot V^2_r + V^2_c = squareroot (12.91)^2 + (26.39)^2 = 29.28 m/s theta = tan^-1(V_r/V_c) = tan^-1(12.91/26.39) = 26.07 degree Velocity = 29.28 m/s Angle of Impact = 26.07 degree