EXAM 1

An Australian emu is running due north in a straight line at a speed of 13.8 m/s and slows down to a speed of 10.2 m/s in 4.5 s. What is the bird's acceleration? (include the sign)

-0.8

C.) 16 m

Keisha looks out the window from a tall building at her friend Monique standing on the ground, 8.3 m away from the side of the building, as shown. If Keisha's line of sight makes a 30° angle with the side of the building, what is Keisha's height above the ground? Assume Monique is 1.5 m tall. A.) 14 m B.) 15 m C.) 16 m D.) 17 m

Suppose that a NASCAR race car is moving to the right with a constant velocity of +70.8 m/s. Twelve seconds later, the car is halfway around the track and traveling in the opposite direction with the same speed. What is the average acceleration of the car?

-11.8

You step onto a hot beach with your bare feet. A nerve impulse, generated in your foot, travels through your nervous system at an average speed of 111 m/s. How much time does it take for the impulse, which travels a distance of 2.02 m, to reach your brain?

0.0182

A bottle of wine known as a magnum contains a volume of 1.76 liters. A bottle known as a jeroboam contains 0.792 U.S. gallons. How many magnums are there in one jeroboam? (1 U.S. gallons = 3.785 liters)

1.7

Vector A has a magnitude of 74.7 units and points due west, while vector B has the same magnitude and points due south. Find the magnitude of A+B.

105.6

A student sees a newspaper ad for an apartment that has 1,205 square feet (ft2) of floor space. How many square meters of area are there? (1 m = 3.281 feet)

112

VW Beetle goes from 0 to 60.4 mi/h with an acceleration of +2.25 m/s2. How much time does it take for the Beetle to reach this speed? (1 mi = 1.609 km)

12

A force vector F1 points due east and has magnitude of 264 newtons. A second force F2 is added to F1. The resultant of the two vectors has a magnitude of 394 newtons and points east. Find the magnitude of F2.

130

An 18-year-old runner can complete a 11.6 km course with an average speed of 4.5 m/s. A 50-year-old runner can cover the same distance with an average speed of 4.16 m/s. How much later (in seconds) should the younger runner start in order to finish the course at the same time as the older runner?

211

A highway is to be built between two towns, one of which lies 38.3 km south and 94 km west of the other. At what angle would this highway be directed with respect to due west?

22.2

A force vector has a magnitude of 480.4 newtons and points at an angle of 27.2° below the positive x axis. What is the y scalar component?

220

The components of vector A are Ax and Ay (both positive), and the angle that it makes with respect to the positive x axis is θ. Find the angle θ if the components of the displacement vector A are Ax = 16.1 m and Ay = 8.5 m.

27.8

In getting ready to slam-dunk the ball, a basketball player starts from rest and sprints to a speed of 6.9 m/s in 1 s. Assuming that the player accelerates uniformly, determine the distance he runs.

3.5

What is the multiplication of 1.48×2.584 with the correct number of significant figures?

3.82

A force vector has a magnitude of 403.3 newtons and points at an angle of 37.7° below the positive x axis. What is the x scalar component?

319

A car is traveling at 19.5 m/s, and the driver sees a traffic light turn red. After 0.455 s (the reaction time), the driver applies the brakes, and the car decelerates at 7.4 m/s2. What is the stopping distance of the car, as measured from the point where the driver first sees the red light?

34.6

A tourist being chased by an angry bear is running in a straight line toward his car at a speed of 3.46 m/s. The car is a distance d away. The bear is 34.7 m behind the tourist and running at 6.59 m/s. The tourist reaches the car safely. What is the maximum possible value for d?

38.4

Vector A has a magnitude of 63.2 units and points due west, while vector B has the same magnitude and points due south. Find the direction of A+B relative to west.

45

A ball is thrown vertically upward, which is the positive direction. A little later it returns to its point of release. The ball is in the air for a total time of 9.5 s. What is its initial velocity? Neglect air resistance. (g = 9.80 m/s2)

46.6

A ball is thrown straight upward. At 3.89 m above its launch point, the ball's speed is one-half its launch speed. What maximum height above its launch point does the ball attain? (g = 9.80 m/s2)

5.19

What is the sum of 1.41 + 2.559 + 3.8 written with the correct number of significant figures?

7.8

A highway is to be built between two towns, one of which lies 26.9 km south and 88.4 km west of the other. What is the shortest length of highway that can be built between the two towns?

92.4

D.)Ax = 0 m and Ay = -450.0 m

A person drives a car for a distance of 450.0 m. The displacement A of the car is illustrated in the drawing. What are the scalar components of this displacement vector? A.)Ax = -450.0 m and Ay = 0 m B.)Ax = -450.0 m and Ay = +450.0 m C.)Ax = +450.0 m and Ay = +450.0 m D.)Ax = 0 m and Ay = -450.0 m E.)Ax = 0 m and Ay = +450.0 m

3

A person is jogging along a straight line, and her displacement is denoted by the vector A in the drawings. Which drawing represents the correct vector components, Ax and Ay, for the vector A?

Before using a warehouse space to install a sculpture, Yasmeen needs to determine the space's volume to see if her large planned sculpture will fit. She measures the height of the space to be 4.1 meters, the width of the space to be 5.24 meters, and the length of the space to be 10.3 meters. What is the volume of the space? Make sure to use significant figures. A.) 220 m^3 B.) 219 m^3 C.) 219.1368 m^3 D.) 219.1 m^2

A.) 220 m^3

If a t-shirt gun can fire t-shirts with an initial speed of 15 m/s, what is the maximum distance (along horizontal, flat ground) a t-shirt can be fired? (g = 9.80 m/s2) A.) 23 m B.) 21 m C.) 30 m D.) 27 m

A.) 23 m

What is a car's average speed if it travels 320 km in 3.6 h? A. 89 km/h B. 88 km/h C. 88.889 km/h D. 87 km/h

A.) 89 km/h

A

Add the three vectors graphically to get the resultant vector - drawing a diagram should help.

If you walk 9 miles due north, then turn around and walk 5 miles due south, how much total distance have you traveled and what is your net displacement from your starting point respectively? A.) 4 miles, 4 miles B.) 14 miles, 4 miles C.) 14 miles, 14 miles D.) 4 miles, 14 miles

B.) 14 miles, 4 miles

You get into your spaceship, blast off from Earth, and travel straight across the Solar System to Saturn for a displacement of 1.27 × 109 km. Assuming your spaceship averaged 1.20 × 104 m/s for the trip to Saturn, how long did this trip take? A.) 1.76 years B.) 3.35 years C.) 17.2 years D.) 20.1 years

B.) 3.35 years

If a primatologist measures a gorilla's mass to be 170.20 kg, how many significant figures are there in her measurement? A.) 6 B.) 5 C.) 4 D.) 3 E.) 2

B.) 5

A ball is dropped from rest and takes 1.3 s to hit the ground. From what height was it dropped? (g = 9.80 m/s2) A.) 7.5 m B.) 8.3 m C.) 13 m D.) 17 m

B.) 8.3 m

Jackie Joyner-Kersee is the American record holder in the long jump with a distance along the ground of 7.49 m. If her take-off angle with the ground was 40o, what was her take-off speed (the magnitude of her take-off velocity)? (g = 9.80 m/s2) A.) 9.78 m/s B.) 8.63 m/s C.) 11.7 m/s D.) 8.21 m/s

B.) 8.63 m/s

What is the difference between distance and displacement? A.)Distance is a vector, while displacement is not a vector. B.)Displacement is a vector, while distance is not a vector. C.)There is no difference between the two concepts; they may be used interchangeably.

B.) Displacement is a vector, while displacement is not a vector.

A rocket is sitting on the launch pad. The engines ignite, and the rocket begins to rise straight upward, picking up speed as it goes. At about 1000 m above the ground the engines shut down, but the rocket continues straight upward, losing speed as it goes. It reaches the top of its flight path and then falls back to earth. Ignoring air resistance, decide which one of the following statements is true. A.)All of the rocket's motion, from the moment the engines ignite until just before the rocket lands, is free-fall. B.)Only part of the rocket's motion, from just after the engines shut down until just before it lands, is free-fall. C.)Only the rocket's motion while the engines are firing is free-fall. D.)Only the rocket's motion from the top of its flight path until just before landing is free-fall. E.)Only part of the rocket's motion, from just after the engines shut down until it reaches the top of its flight path, is free-fall.

B.) Only part of the rocket's motion, from just after the engines shut down until just before it lands, is free-fall.

Which of the following is not a vector? A.) Force B.) Time C.) Acceleration D.) Displacement

B.) Time

A self-driving car and one driven by a person are both initially traveling at 60 mi/h along a straight road. Suddenly, a cow wanders onto the road ahead. The person sees the cow and steps on the brakes after 0.25 seconds, while the robotic system in the self-driving care "sees" the cow and starts braking after 0.50 seconds. How much further has the self-driving car traveled before it starts braking? (5280 ft = 1 mi). A.) 15 ft B.) 20 ft C.) 22 ft D.) 31 ft

C.) 22 ft

If a rocket accelerates at a uniform 16 m/s2, how long will it take to reach a speed of 1800 km/hr if it starts from rest? A.) 11 s B.) 18 s C.) 31 s D.) 110 s

C.) 31 s

Vector S has magnitude 4 m and is directed to the south. Vector E has magnitude 3 m and is directed to the east. What are the magnitude and direction of S - E? A.) 5 m, southeast B.) 1 m, southwest C.) 5 m, southwest D.) 1 m, southeast

C.) 5 m, southwest

A teenager on a motor bike travels for 3.5 h at 50 km/h and 2.5 h at 70 km/h. What is her average speed for the trip? A). 20 km/h B.) 54 km/h C.) 58 km/h D.) 60 km/h

C.) 58 km/h

Four runners completed a relay race where they each ran 800 m (for a total of 3200 m). If their times were 1 minute 55 seconds, 2 minutes 2 seconds, 1 minute 58 seconds, and 1 minute 52 seconds, what was the average speed for the entire race? A.) 2.37 m/s B.) 4.80 m/s C.) 6.85 m/s D.) 7.81 m/s

C.) 6.85 m/s

Driving along interstate 75 through The Everglades ("Alligator Alley") at 108 km/hr, you look out the window and spot an alligator resting in the sun before returning your attention to the road. If you were looking out the window for 2.1 seconds, how much distance did you cover while looking at the alligator? A.) 18 m B.) 51 m C.) 63 m D.) 230 m

C.) 63 m

A jogger runs along a straight and level road for a distance of 8.0 km and then runs back to her starting point. The time for this round-trip is 2.0 h. Which one of the following statements is true? A.)Her average speed is 8.0 km/h, but there is not enough information to determine her average velocity. B.)Her average speed is 8.0 km/h, and her average velocity is 8.0 km/h. C.)Her average speed is 8.0 km/h, and her average velocity is 0 km/h.

C.) Her average speed is 8.0 km/h, and her average velocity is 0 km/h

In which one of the following situations can the equations of kinematics not be used? A.)When the velocity changes from moment to moment, B.)when the velocity remains constant, C.)when the acceleration changes from moment to moment, D.)when the acceleration remains constant.

C.) when the acceleration changes from moment to moment,

A potato is thrown straight upwards with a speed of 10 m/s. How long does it take to reach a height 2.2 m above where it started while descending (on the way down)?Neglect air resistance, and assume the acceleration due to gravity is g = 9.8 m/s2. A.) 0.22 s B.) 0.25 s C.) 1.5 s D.) 1.8 s

D.) 1.8 s

Serena and Venus Williams start 150 m apart and begin running towards each other. Serena has a speed of 7.5 m/s and Venus has a speed of 5.0 m/s. How long does it take for them to meet? A.) 9 s B.) 10 s C.) 11 s D.) 12 s

D.) 12 s

A cyclist cycles 7 km west and then 12 km north. What is the magnitude of her displacement vector? A.) 10 km B.) 5 km C.) 19 km D.) 14 km

D.) 14 km

A regulation soccer ball has a diameter of about 22.0 cm. What is the approximate circumference of this ball in inches (in)? A.) 13.6 in B.) 175 in C.) 69.1 in D.) 27.2 in

D.) 27.2 in

A catapult launches a rock with an initial speed of 35 m/s at an initial angle of 22o above the ground from a height of 0.0 m. After the rock has traveled 10 m horizontally along the ground from its starting point, what is its height above the ground? (g = 9.80 m/s2) A.) 3.7 m B.) 4.1 m C.) 5.0 m D.) 3.6 m

D.) 3.6 m

Cosmic rays are highly energetic particles which can travel at great speeds through outer space. A typical speed for a cosmic ray is 1.29 x 108 m/s. What is this speed converted to km/hr (kilometers per hour)? A.) 1.29 x 10^5 km/hr B.) 35.8 km/hr C.) 7.74 x 10^6 km/hr D.) 4.64 x 10^8 km/hr

D.) 4.64 x 10^8 km/hr

Starting at the same time, an arrow and a ball are shot horizontally with a speeds of 50 m/s and 44 m/s respectively from the top of a building over flat ground. Which best describes what happens? A.) The arrow and the ball land the same distance from the building at different times. B.) The arrow and the ball land at different distances from the building at different times. C.) The arrow and the ball land the same distance from the building at the same time. D.) The arrow and the ball land at different distances from the building at the same time.

D.) The arrow and the ball land at different distances from the building at the same time.

A velocity vector V has magnitude 11 m/s and has an angle of 35o below the negative x axis. What are this vector's x and y components? Drawing a diagram should help. A.) Vx = 9.0 m/s ; Vy = 6.3 m/s B.) Vx = -6.3 m/s ; Vy = 9.0 m/s C.) Vx = 6.3 m/s ; Vy = 9.0 m/s D.) Vx = -9.0 m/s ; Vy = -6.3 m/s

D.) Vx = -9.0 m/s ; Vy = -6.3 m/s

4

During a relay race, runner A runs a certain distance due north and then hands off the baton to runner B, who runs for the same distance in a direction south of east. The two displacement vectors A and B can be added together to give a resultant vector R. Which drawing correctly shows the resultant vector?

3

The first drawing shows the sum of three displacement vectors, A, B, and C. The resultant vector is labeled R. Which of the following drawings shows the correct resultant vector for A - B - C?

2

The first drawing shows three displacement vectors, A, B, and C, which are added in a tail-to-head fashion. The resultant vector is labeled R. Which of the following drawings shows the correct resultant vector for A + B - C?

A.) A right, B left, C right

The graph accompanying this problem shows a three-part motion. For each of the three parts, A, B, and C, identify the direction of the motion. A positive velocity denotes motion to the right. A.)A right, B left, C right B.)A right, B right, C left C.)A right, B left, C left D.)A left, B right, C left E.)A left, B right, C right

2.26

The three displacement vectors in the drawing have magnitudes of A = 4.22 m, B = 4.22 m, and C = 3.81 m. Find the magnitude of the resultant of the three vectors.

137.39

The three displacement vectors in the drawing have magnitudes of A = 5.04 m, B = 5.04 m, and C = 4.05 m. Find the direction of the resultant of the three vectors. Express the directional angle as an angle above the positive x axis (counterclockwise with respect to the positive x axis).