What are the magnitude Δ? and angle ? of the change in velocity if the initial velocity is 15.0 m/s south and the final velocity is 70.0 m/s west? Let the angle ? be measured relative to the east direction (e.g., ?=90∘ means Δ? points north, ?=180∘ means Δ? points west, etc.).

Ex. 3. A car is moving with a velocity of 15 m/s [E]. It makes a turn steadily in 5.0s so that the velocity is 12 m/s [E 25° N]. Determine the average acceleration of the car.

*61. O A person looking out the window of a station- ary train notices that rain- drops are falling vertically down at a speed of 5.0 m/s relative to the ground. When the train moves at a constant 25 velocity, the raindrops make an angle of 25° when they move past the window, as the drawing shows. How fast is the train moving?

= 17.5 m/s. The cliff is h = 32.0 m above a flat, horizontal beach as shown in the figure. A student stands at the edge of a cliff and throws a stone horizontally over the edge with a speed of х (a) What are the coordinates of the initial position of the stone? Xo = Уо- (b) What are the components of the initial velocity? Vox = m/s m/s Vov= (c) Write the equations for the x- and y-components of the velocity of the stone with time. (Use the following as necessary: t. Let the variable t be measured in seconds. Do not include units in your answer.) Vx= Vy= (d) Write the equations for the position of the stone with time, using the coordinates in the figure. (Use the following as necessary: t. Let the variable t be measured in seconds. Do not state units in your answer.) х3 (e) How long after being released does the stone strike the beach below the cliff? (f) With what speed and angle of impact does the stone land? m/s Ve= • below the horizontal Ө-