Physics 1 - preAP2 – Dimensional and Relative Motion Problem Set

AS USUAL, DO NOT SHOW WORK ON THIS PAGE. SHOW WORK ONLY ON YOUR OWN PAPER.

Part I: Horizontal Launch

  1. Divers at Acapulco dive from a cliff that is 60 m high. If the rocks below the cliff extend outward for 20 m, what is

the minimum horizontal velocity a diver must have to clear the rocks safely and what is their velocity as they enter the water? (5.7 m/s)

  1. A dart player throws a dart horizontally at a speed of 12 m/s. The dart hits the board 0.3 m below the height from

which it was thrown. How far away is the player from the board? (2.9 m)

3. A toy car rolls off the edge of a platform with a velocity of 2.5 m/s. The car hits the ground 4.5 m from the end of the platform. How high above the ground is the platform? What is the velocity at impact? (16 m)

4. Two youngsters dive off an overhang into a lake. Diver 1 drops straight down, diver 2 runs off the cliff with an initial horizontal speed vo. Is the splashdown speed of diver 2 (a) greater than, (b) less than, or (c) equal to the splashdown speed of diver 1?

5. A mountain climber encounters a crevasse in an ice field. The opposite side of the crevasse is 2.75 m lower, and is separated horizontally by a distance of 4.10 m. To cross the crevasse, the climber gets a running start and jumps in the horizontal direction. What is the minimum speed needed to safely cross the distance? (5.48 m/s)

6. Libyan basketball player Suleiman Nashnush was the tallest basketball player ever. His height was 2.45 m. If a basketball was thrown horizontally from a level equal to the top of his head, and it landed with a velocity of

12.0 m/s, what was the ball’s initial speed? (Hint: consider components of final velocity.) (9.8 m/s)

TEXT - p. 115: 36, 37

Part II: Launched at any angle

  1. A projectile has an initial velocity of 20 m/s at an angle of 53o above the horizontal. Find:

a)The maximum height of its trajectory. (13 m)

b)The range of its trajectory. (38 m)

c)The horizontal distance from the starting point after 2.0 s. (24 m)

d)The vertical distance from the starting point after 2.0 s. (12 m)

e)How long is it in the air? (3.2 s)

A batter hitting a fly ball gives it an initial velocity of 30 m/s at an angle of 30o with the level ground.

How far from the batter will the ball land on the ground? (78 m)

  1. A famous motorcyclist plans to jump across a canyon 3.5 km wide. To do this, he plans to leave a

30o ramp on one side of the canyon at a speed of 196 m/s. If he attains this speed, will he

reach the other side of the canyon on the jump or do we send flowers?

  1. A player kicks a ball at an angle of 37o with the horizontal and with an initial velocity of 15 m/s.

A second player standing at a distance of 30 m from the first (in the direction of the kick) starts running to meet the ball at the instant it is kicked. How fast must he run in order to catch the ball before it hits the ground? (4.7 m/s)

4. A football game begins with a kickoff in which the ball travels a horizontal distance of 41 m and lands on the

ground. If the ball was kicked at an angle of 40.0o above the horizontal, what was its initial speed? (20 m/s)

5. Chipping from the rough, a golfer sends the ball over a 3.00 m high tree that is 14.0 m away. The ball lands at the same level from which it was struck after traveling a horizontal distance of 17.8 m . (a) If the ball left the club 54.0o above the horizontal and landed on the green 2.24 s later, what was its initial speed) (b) How high was the ball when it passed over the tree? (13.5 m/s 4.03 m)

6. A golfer hits a ball from the origin (the tee) with an initial speed of 30.0 m/s at an angle of 50.0o above the horizontal. The ball lands on a green that is 5.00 m above the level where the ball was struck.

a. How long is the ball in the air? (4.46 s)

b. What is the ball’s range when it lands? ( 86.0 m)

c. What is the velocity when the golf ball lands? (28.4 m/s; θ = 47.1o below the horizontal)

7. Suppose a football is punted at an angle of 37.0o with a velocity of 20.0 m/s at a height of 1.00 m above the ground. How far did the football travel before hitting the ground? ( 40.5 m)

TEXT - p. 115 #38, 39, 41

Part III: Relative Motion: Text p. 109 (Practice set) #1,4

p. 116 #47 - 51