Vectors and Projectiles Problems MC Questions y vo

Vectors and Projectiles Problems MC Questions y vo q L h R x d vw v. B

01 The resultant of two vectors is the smallest when the angle between the two vectors is (A) 0° (B) 45° (C) 90° (D) 180°.

02 Two vectors, of magnitudes 20 and 50, are added. Which one of the following is a possible answer for the magnitude of the resultant? (A) 10 (B) 20 (C) 40 (D) 80

03 An airplane with a speed of 120 km/h is headed 30. 0° east of north in a wind blowing due west at 30. 0 km/h. What is the speed of the plane relative to the ground? (A) 90. 0 km/h (B) 110 km/h (C) 137 km/h (D) 150 km/h

04 An Olympic athlete throws a javelin at four different angles above the horizontal, each with the same speed: 30°, 40°, 60°, and 80°. Which two throws cause the javelin to land the same distance away? (A) 30° and 80° (B) 40° and 60° (C) 40° and 80° (D) 30° and 60°

05 A plane flying horizontally at a speed of 50. 0 m/s and at an elevation of 160 m drops a package. Two seconds later it drops a second package. How far apart will the two packages land on the ground? (A) 100 m (B) 162 m (C) 177 m (D) 283 m

06 A projectile is launched with an initial velocity of 60. 0 m/s at an angle of 30. 0° above the horizontal. What is the maximum height reached by the projectile? (A) 23 m (B) 46 m (C) 69 m (D) 92 m

07 A swimmer heading directly across a river 200 m wide reaches the opposite bank in 6 min 40 s. She is swept downstream 480 m. What is the speed of the current? (A) 0. 50 m/s (B) 1. 2 m/s (C) 1. 4 m/s (D) 1. 8 m/s

08 If you walk 6. 0 km in a straight line in a direction north of east and you end up 2. 0 km north and several kilometers east. How many degrees north of east have you walked? (A) 19° (B) 45° (C) 60° (D) 71°

09 A ball thrown horizontally from a point 24 m above the ground, strikes the ground after traveling horizontally a distance of 18 m. With what speed was it thrown? (A) 6. 1 m/s (B) 7. 4 m/s (C) 8. 1 m/s (D) 8. 9 m/s

10 The driver of a motorboat that can move at 10 m/s in still water wishes to travel directly across a narrow strait in which the current flows at 5. 0 m/s. At what angle upstream should the driver head the boat? (A) 27° (B) 30° (C) 60° (D) 63°

11 At what angle should a water-gun be aimed in order for the water to land with the greatest horizontal range? (A) 0° (B) 30° (C) 45° (D) 60°

12 Your motorboat can move at 30 km/h in still water. How much time will it take you to move 12 km downstream, in a river flowing at 6. 0 km/h? (A) 20 min (B) 22 min (C) 24 min (D) 30 min

13 A runner runs halfway around a circular path of radius 10 m. What is the displacement of the jogger? (A) 0 (B) 5 m (C) 10 m (D) 20 m

14 If a ball is thrown with a velocity of 25 m/s at an angle of 37° above the horizontal, what is the vertical component of the velocity? (A) 12 m/s (B) 15 m/s (C) 19 m/s (D) 25 m/s

15 A car travels 20 km west, then 20 km south. What is the magnitude of its displacement? (A) 0 km (B) 20 km (C) 28 km (D) 40 km

16 A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. A stop watch measures the stone's trajectory time from the top of the cliff to the bottom to be 4. 3 s. What is the height of the cliff? (A) 22 m (B) 43 m (C) 77 m (D) 91 m

17 A jumper in the long-jump goes into the jump with a speed of 12 m/s at an angle of 20° above the horizontal. How far does the jumper jump? (A) 3. 4 m (B) 6. 2 m (C) 9. 4 m (D) 15 m

18 A projectile is launched with an initial velocity of 60. 0 m/s at an angle of 30. 0° above the horizontal. How far does it travel? (A) 152 m (B) 160 m (C) 184 m (D) 318 m

19 On a calm day (no wind), you can run a 1500 -m race at a velocity of 4. 0 m/s. If you ran the same race on a day when you had a constant headwind which slows your speed by 2. 0 m/s, the time it would take you to finish would be (A) 250 s. (B) 750 s. (C) 1125 s. (D) 9000 s.

20 A girl throws a rock horizontally, with a velocity of 10 m/s, from a bridge. It falls 20 m to the water below. How far does the rock travel horizontally before striking the water? (A) 14 m (B) 16 m (C) 20 m (D) 24 m