PART C: Multiple Choice /10] 1. (K) A ball is thrown to the north and is experiencing projectile motion. What are the directions of the acceleration and instantaneous velocity, respectively, of the ball at maximum height (e.g., the peak of its trajectory)? a) north, north b) up, north c ) north, down d) north, down e ) down, down 2. (K) A cyclist cycles 50.0 km [N] and then 30.0 km [E]. The total time taken for the trip is 1.00 h. What is its average velocity? a) 3.40 x 10 3 km/h [31. E of N] b) 58.3 km/h [310 E of N] c ) 3.40 x 10 3 km/h [59 E of N] d) 58.3 km/h [590 E of N] e ) 58.3 km/h [NE ] 3. (K) A car is travelling west and approaching a stop sign. As it is slowing to a stop, the directions associated with the object's velocity and acceleration, respectively, are [W], [E] b) [W]. [W] c) [E], [E] d) [E], [W] e ) There is not enough information to tell. 4. (K) The direction equivalent to - [40 W of S] is [40 E of S] b) [40 W of N] c) [40 E of N] d) [50 S of W] e ) [50 E of N] 5. (K) If a car travelling at 60.0 km/h [S] stops in a time of 3.50 s, its acceleration is: 4.77 m/s? [S] b ) 4.77 m/s? [N] c) 16.7 m/s' [S] d) 16.7 m/s' [N] e ) 17.1 m/s? [S] pg. 2 6. (K) Which of the following objects are in "free fall"? a) a ball that was thrown horizontally b ) a ball that was thrown at an angle above horizontal c) a ball that was thrown at an angle below horizontal d) a ball that was dropped e) all of the above 7. (K) A baseball player is trying to determine her maximum throwing distance. She must release the ball: a) at an angle that lets the ball reach the highest possible height b ) horizontally c ) at an angle of 450 d) so that it has maximum possible speed, regardless of angle e) at an angle between 45 and 90 8. (K) An airplane is flying to a city due south from its current location. If there is a slight wind blowing to the south-east, the plane must head (point) to the: a ) south b) west c ) south-west d) south-east e ) east (K) A ball is thrown up in the air and then caught at the same height. The acceleration is 9.8 m/s2 [down]: on the w b ) on the way down c) at the peak of its trajectory d) two of A, B, and C are correct e) all of A, B, and C are correct 10. (K) A boy throws a ball off of a second floor balcony by throwing it up into the air at some angle above horizontal. It comes back down, landing on the ground. Neglecting air resistance, the magnitude of velocity is greatest: a) just after it leaves the boy's hand b ) at the peak of the ball's trajectory c ) just before it hits the ground d) it remains the same throughout the motion e) impossible to tell without knowing the angle of projection