INSTITUTO TECNOLÓGICO DE SANTO DOMINGOAREA DE CIENCIAS BÁSICAS Y AMBIENTALES

FISICA I PRACTICA IIIGRAFICOS CINEMATICA

MM ATRÍCULA ________________NOMBRE__________________________________________PROF. VINICIO ROMERO

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

1) A skier begins skiing straight down a hill having a constant slope, starting from rest. If friction isnegligible, as the skier goes down the hill, his/her

1)

A) acceleration is constant, with a value less than 10 m/s/s.B) acceleration is zero.C) acceleration is constant, with a value of roughly 10 m/s/s.D) acceleration increases with time.

2) A person in a car is driving down a straight road. The instaneous acceleration is decreasing withtime, but is directed in the direction of the car's motion. The speed of the car is

2)

A) increasing with time. B) constant. C) decreasing with time.

3) The plot below shows the position of an object as a function of time. The letters H-L representparticular moments of time. At which moment in time is the speed of the object the highest?

3)

A) K B) L C) H D) J E) I

4) Two identical stones are dropped from a tall building, one after the other. Assume air resistance isnegligible. While both stones are falling, what will happen to the vertical distance between them?

4)

A) It will increase.B) It will first increase and then remain constant.C) It will remain the same.D) It will decrease.

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5) A trolley starts from rest and runs down a sloping track section onto a second level section asshown. Friction is negligible.

Which velocity-time graph below best represents the trolley's motion on both sections? Justify youranswer.

5)

A) B)

C) D)

6) The motions of a car and a truck along a straight road are represented by the velocity-time graphsbelow. The two vehicles are initially alongside each other at time t = 0.

At time T, what is true of the distances travelled by the vehicles since time t = 0?

6)

A) The car will have travelled further than the truck.B) The truck will have travelled further than the car.C) They will have travelled the same distance.D) The truck will not have moved.

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Figure 2.3

7) An object is moving in a straight line (the x-axis). The graph in Fig. 2.3 shows the x-coordinate ofthis object as a function of time. Which one of the following statements about this object is correct?

7)

A) Between points A and B, the x-component of its average velocity is 0.75 m/s, but its averagespeed is less than 0.75 m/s.

B) Between points A and B, both the x-component of its average velocity and its average speedare greater than 0.75 m/s.

C) Between points A and B, both the x-component of its average velocity and its average speedare equal to 0.75 m/s.

D) Between points A and B, both the x-component of its average velocity and its average speedare less than 0.75 m/s.

E) Between points A and B, the x-component of its average velocity is 0.75 m/s, but its averagespeed is greater than 0.75 m/s.

2-7

8) Figure 2-7 represents the position of a particle as it travels along the x-axis. What is the magnitudeof the average velocity of the particle between t = 1 s and t = 4 s?

8)

A) 0.50 m/s B) 0.67 m/s C) 1.0 m/s D) 0.25 m/s E) 1.3 m/s

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FIGURE 2-8

9) Figure 2-8 represents the position of a particle as it travels along the x-axis. At what value of t isthe speed of the particle equal to zero?

9)

A) 4 s B) 2 s C) 1 s D) 3 s E) 0 s

10) Figure 2-8 represents the position of a particle as it travels along the x-axis. How does theinstantaneous speed of the particle when t = 2 s compare with its speed when t = 4 s?

10)

A) The speed at t = 2 s is smaller.B) The speed at t = 2 s is larger.C) They are about equal.D) The speed at t = 2 s is the negative of the speed at t = 4 s.E) The speed at t = 4 s is the negative of the speed at t = 2 s.

FIGURE 2-9

11) Figure 2-9 represents the velocity of a particle as it travels along the x-axis. What is the averageacceleration of the particle between t = 1 second and t = 4 seconds?

11)

A) 2.0 m/s2 B) 3.0 m/s2 C) 1.7 m/s2 D) 0.33 m/s2 E) 2.5 m/s2

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FIGURE 2-10

12) Figure 2-10 shows the velocity-versus-time graph for a basketball player traveling up and downthe court in a straight-line path. Find the net displacement of the player for the 10 s shown on thegraph.

12)

A) 14 m B) 12 m C) 20 m D) 16 m E) 18 m

13) Figure 2-10 shows the velocity-versus-time graph for a basketball player traveling up and downthe court in a straight-line path. Find the total distance run by the player in the 10 s shown in thegraph.

13)

A) 16 m B) 14 m C) 12 m D) 18 m E) 20 m

14) The slope of a line connecting two points on a position versus time graph gives 14)A) instantaneous velocity.B) average accelerationC) average velocity.D) instantaneous acceleration.E) none of the given answers.

15) The slope of a tangent line at a given time value on a velocity versus time graph gives 15)A) instantaneous velocity.B) average accelerationC) average velocity.D) instantaneous acceleration.E) none of the given answers.

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FIGURE 2-1

16) Which graph in Fig. 2-1 represents an object at rest? 16)A) graph aB) graph bC) graph cD) graph dE) both graphs a and d

FIGURE 2-2

17) Which graph in Fig. 2-2 represents a constant non-zero velocity? 17)A) graph aB) graph bC) graph cD) graph dE) both graphs c and d

18) Which graph(s) in Fig. 2-2 represent(s) zero acceleration? 18)A) only a B) only b C) a and b D) b and c E) c and d

19) Which graph(s) in Fig. 2-2 represent(s) constant positive acceleration? 19)A) graph aB) graph bC) graph cD) graph dE) both graphs c and d

20) For constant linear acceleration, the position versus time graph is a 20)A) vertical line.B) curve.C) horizontal line.D) sloped line.E) none of the given answers.

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21) For constant linear acceleration, the velocity versus time graph is a 21)A) curve.B) horizontal line.C) vertical line.D) sloped line.E) none of the given answers.

FIGURE 2-3

22) The graph in Fig. 2-3 plots the velocity of two cars (A and B) along the same straight road. Duringthe time interval shown, which car is AHEAD?

22)

A) Car A B) Car B C) insufficient information

23) The graph in Fig. 2-3 plots the velocity of two cars (A and B) along the same straight road. Whichcar reverses direction?

23)

A) insufficient informationB) Car AC) Car BD) both cars A & BE) neither car A nor B

FIGURE 2-4

24) During the first 8 s in Fig. 2-4, 24)A) D is speeding up while C is slowing downB) the magnitude of the acceleration of D is greater than the magnitude of the acceleration of C.C) their accelerations are equal in magnitude, and equal in sign.D) the magnitude of the acceleration of C is greater than the magnitude of the acceleration of D.E) their accelerations are equal in magnitude, but opposite in sign.

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25) (Refer to Fig. 2-4.) At t = 0 s 25)A) rider D is moving faster than rider C.B) rider C is ahead of rider D.C) rider D is moving slower than rider C.D) rider D is ahead of rider C.E) riders C and D are at the same position.

26) (Refer to Fig. 2-4.) At t = 1 s 26)A) C and D are both moving.B) C is ahead of DC) D is moving, and C is at rest.D) C is moving, and D is at rest.E) C and D are both at rest.

27) (Refer to Fig. 2-4.) At t = 1 s 27)A) D has a greater velocity than C.B) C is accelerating.C) D is accelerating.D) C has a greater velocity than D.E) C and D have the same velocity.

28) (Refer to Fig. 2-4.) At t = 10 s 28)A) C and D are at the same position.B) C and D have the same velocity.C) D is in front of C.D) C is in front of D.E) the velocity of D is greater than the velocity of C.

FIGURE 2-8

29) (Refer to Fig. 2-8.) Based on all the graphical information 29)A) C and D will meet at the same position at t = 10 s.B) C and D meet at the same position at t = 8 s.C) C and D will never meet at the same position.D) not enough information is given to decide if C and D meet.E) the acceleration of D is negative.

30) (Refer to Fig. 2-8.) During the first 8 s 30)A) C and D have constant velocities.B) C and D are both slowing down.C) the acceleration of D is negative.D) C is slowing down, and D is speeding up.E) C has the same average velocity as D.

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FIGURE 2-1

31) Fig. 2-1 shows the position of an object as a function of time. During which time interval is theobject at rest between 0.0 s and 9.0 s?

31)

A) The object is at rest between 0.0 s and 3.0 s.B) The object is at rest between 3.0 s and 6.0 s.C) The object is never at rest.D) The object is at rest between 6.0 s and 9.0 s.E) The object is always at rest except at the instants t = 3.0 s and t = 6.0 s.

FIGURE 2-2

32) The motion of a particle is described in the velocity vs. time graph shown in Fig. 2-2. We can saythat its speed

32)

A) remains constant.B) increases.C) increases and then decreases.D) decreases and then increases.E) decreases.

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FIGURE 2-3

33) Fig. 2-3 shows the velocity of an object as a function of time. Which graph best represents theacceleration as a function of time?

33)

A)

B)

10

C)

D)

E) none of the above

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FIGURE 2-4

34) A graph of position as a function of time is shown in Fig. 2-4. During which time interval couldthe object be possibly moving with non-zero constant acceleration?

34)

A) 6.1 s to 7.9 sB) 0.1 s to 1.9 sC) 4.1 s to 5.9 sD) 2.1 s to 3.9 sE) There is no interval that is consistent with constant non-zero acceleration.

FIGURE 2-5

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35) A plot of position as a function of time is shown in Fig. 2-5. Which graph represents theacceleration as a function of time?

35)

A)

B)

C)

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D)

E)

36) Which graph below could represent the motion of the object described in the following sentences?The object that starts its motion with a constant velocity of 2.0 m/s east. After 3.0 s, the object stopsfor 1.0 s. The object then moves toward the west a distance of 2.0 m in 3.0 s. The object continuestraveling in the same direction, but increases its speed by 1.0 m/s for the next 2.0 s.

36)

A)

14

B)

C)

D)

E) None of the above graphs could represent the motion described.

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37) Which of the following graphs could possibly represent the motion as a function of time of anobject in free fall?

37)

A)

B)

C)

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D)

E)

FIGURE 2-10

38) Fig. 2-10 shows the position of an object as a function of time. What is the length of the path theobject followed during the time interval from time t = 0.0 s and time t = 9.0 s?

38)

A) -1.0 m B) 3.0 m C) 5.0 m D) 19.5 m E) 1.0 m

39) Fig. 2-10 shows the position of an object as a function of time. What is the average speed of theobject between time t = 0.0 s and time t = 9.0 s?

39)

A) -0.11 m/s B) 0.11 m/s C) 0.33 m/s D) -0.33 m/s E) 0.56 m/s

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