A helicopter blade spins at exactly 130 revolutions per minute. Its tip is 7 m from the center of rotation. Hint: What is the shape of the path described by the helicopter blade? How do you find the length of this path?  (a) What is the total distance traveled by the tip per minute? Distance:  m (b) What is the average speed of the tip of the blade?  Average speed:  m/s (c) What is the average velocity over one revolution? Average velocity:  m/s

You can use the formula for centripetal acceleration OR You have to calculate the average acceleration directly from the definition, a = delta v / delta t.  You have to first get a_x by using the velocity's initial and final x components, do a_y from the y components, and then use the Pythagorean formula to get the magnitude of the acceleration vector.

The figure shows thes initial position i and the final position f of a particle. 4 m i 3 m 3 m 4 m 4m 3 m 5m 3m 2 m 1m What is the initial position vector in unit-vector notation? n 2 m/ Xy 1m! 4m 5m 3 m x .i 3m m î+ i m + i mk

You built a pinball machine that has a banked circular track with radius 0.34 m. The ball shooter launches the ball directly into this circular track before the ball enters into the game. You fire pin balls at a constant speed into the track and adjust the banking angle until it works. The banking angle is 21 degrees. Assume your pin ball machine is on a horizontal plane, how fast is the ball launched into the track, in m/s? Hint: I have a video on this problem about swing pendulum but the results are very similar, except a string length was given instead of path radius and tension was present instead of normal force. Assume friction is negligible.