# Physics Principles and Problems 2009

## Chapter 2: Representing Motion

### Chapter Test Practice

 1 A(n) __________ is a series of images of a moving object that records its position after equal time intervals. Need a Hint? A) frame B) operational definition C) motion diagram D) association 2 The vector that represents the sum of two or more vectors is called the __________. Need a Hint? A) displacement B) speed C) resultant D) direction 3 In the particle model, the __________ of the object are (is) ignored. Need a Hint? A) internal motions B) motion diagram C) position D) acceleration 4 The length of the position vector on a motion diagram is proportional to the __________. Need a Hint? A) distance of the object from the origin B) distance of the object from the vertical intercept C) average speed D) velocity 5 A motion diagram is a series of images of a moving object that records its position after __________. Need a Hint? A) 1/30 s B) equal time intervals C) it comes to rest D) an acceleration 6 The __________ is the point at which all variables in a coordinate system have zero magnitude. Need a Hint? A) axis B) origin C) intercept D) coordinate system 7 Which of the following correctly describes the displacement of an object that moves from position di to df? Need a Hint? A) Δd = df - di B) v = Δd/Δt C) Δdf = di - df D) Δd = df + di 8 Which of the following is not a scalar quantity? Need a Hint? A) 314.7 g B) 150 km southwest C) 25°C D) 2 hours 27 minutes 9 To subtract two vectors, __________. Need a Hint? A) reverse the direction of the second vector and then add them B) use the equation R2 = A2 - B2 C) use the same process as for adding them, then change the sign of the final value D) subtract 180° from θ, then use the Law of Cosines 10 Displacement is a change in __________. Need a Hint? A) speed B) position C) distance D) velocity 11 The magnitude of a vector is always __________. Need a Hint? A) a positive quantity B) equal to the direction C) equal to the displacement D) a negative quantity 12 When an object is in motion, its __________ must change. Need a Hint? A) position B) shape C) size D) acceleration 13 Two displacements are equal when __________. Need a Hint? A) the two magnitudes and directions are the same B) the two directions are the same C) they end at the same point D) they begin at the same point 14 The difference between ti and tf is the __________. Need a Hint? A) displacement B) velocity C) time interval D) average speed 15 To calculate the distance traveled continuously in a straight line, __________. Need a Hint? A) divide the distance traveled by the time needed to travel the distance B) subtract the cosine of the angle between the starting and finishing positions from the square of the distance traveled C) divide the change in velocity by the time over which the change occurs D) subtract starting position from final position. 16 A(n) __________ tells you where the zero point of the variable you are studying is located and the direction in which the values increase. Need a Hint? A) coordinate system B) origin C) axis D) intercept 17 On a position-time graph, run = __________. Need a Hint? A) Δa B) Δv C) Δt D) Δd 18 On a position-time graph, rise = __________. Need a Hint? A) Δd B) Δt C) Δs D) Δv 19 You and a friend leave school at the same time. You drive at a constant 5.5x10^1 km/h and your friend drives 7.0×10^1 km/h. How long does it take each car to reach a mall that is 25 km from the school? Need a Hint? A) you: 1 hour 40 minutes, your friend 36 minutes B) you: 2.2 hours, your friend: 2.8 hours C) you: 27 minutes, your friend: 21 minutes D) you: 21 minutes, your friend: 27 minutes 20 You drive a car for 2.0 h at 60 km/h, then for another 3.0 h at 85 km/h. What is your average velocity? Need a Hint? A) 75 km/h2 B) 73 km/h C) 75 km/h D) 73 km/h 21 The slope of the line tangent to the curve on a position-time graph at a specific time is the __________. Need a Hint? A) instantaneous acceleration B) instantaneous velocity C) average velocity D) displacement 22 Extrapolating from the graph below, where would the object be at t = 7 s? (6.0K) Need a Hint? A) 15 meters B) -15 meters C) - 7 meters D) - 10 meters 23 The __________ is the ratio of the total distance traveled to the time interval. Need a Hint? A) displacement B) average speed C) acceleration D) instantaneous velocity 24 Based on the graph below, what is the object's velocity at t = 4 s?lc (6.0K)lc Need a Hint? A) 0 m/s B) 5 m/s C) -5 m/s D) 4 m/s 25 Which of the following equations can be used to find the position of an object moving at constant velocity? Need a Hint? A) d = df - vt B) Δd = df - di C) df = di + vt D) tan θ = Ry/Rx