PHYS 2305
Assume the trajectory featured in Figure 4.6b (p. 84) is of a ball thrown near the surface of the Earth, and the y axis points vertically upward. Is the ball only under the influence of gravity? Yes or No?
No
According to your textbook, which of the following statements is true about g?I.) g is a force II.) g is the magnitude of the free fall acceleration of all objects on earth III.) g has both magnitude and direction
II only
A __________ is a composite image showing an object's position at several equally spaced instants of time. a) Motion Diagram b) Frame c) Particle diarama d) Position-vs-time graph
Motion Diagram
Referring to Figure 4.10 (p. 86), which launch angle will allow the ball to travel the largest horizontal distance before landing on the ground? a) 15 degrees b) 30 degrees c) 45 degrees d) 60 degrees e) 75 degrees
45 degrees
In Figure 12.42 (p. 316), suppose a fifth object was included in the downhill race. This object is a spherical shell of radius R and mass M. In what place would the spherical shell finish? 1st-5th
4th
Figure 10.21 (p. 246) shows a particle's potential energy as a function of its position. When is the force on the particle nonzero and only pointing in the negative x-direction? (Choose all that apply). a) Between positions x2 and x3 b) Between positions x3 and x4 c) Before position x2 d) After position x4
A and D
In Stop to Think 6.1 (p. 137), which of the Free Body Diagram choices would result in an acceleration in the upward direction? Check ALL that apply. A B C D E
A and D
If "Stop to Think 3.2" (p 69) instead asked "Which figure shows A+B", which answer would be correct?
C
In Stop to Think 7.2 (p. 166), suppose the question stated: "A large truck backs up into a smaller car that's parked. The mass of the truck is larger than the mass of the car." For this situation, which of the choices given in Stop to Think 7.6 would be correct? A B C D E
C
In Example 9.4 (p. 216), which of the following modifications would leave the dot product of vectors A and B unchanged? (Check all that apply) a) Flipping the direction of vector A b) Flipping the direction of vector B c) Flipping the directions of both vectors A and B d) Rotating vector A counterclockwise by 120 degrees e) Rotating both vectors A and B clockwise by 50 degrees
C and E
True or False: If an object's velocity changes, the object is undergoing uniform motion.
False
True or False: In the absence of air resistance, any two objects dropped at the same height at the same time fall at the same rate and hit the ground at the same time.
True
In which of the following situations is the object in equilibrium? (Check ALL that apply) a) An object with constant velocity b) An object with a constant position c) An object with constant acceleration d) An object undergoing uniform circular motion
a and b
In Figure 4.21 (p. 92), a particle is in uniform circular motion. Assume a standard rtz coordinate system. If you deconstruct the net force acting on the particle along each of these axes (r (radial), t (tangential), and z (perpendicular to the plane of motion), how many non-zero force components exist? a) 1 b) 2 c) 3 d) Zero- There is no net force on a particle in uniform circular motion
a) 1
The rate of spin of a disk is decreasing. A point on the disk that is near the rim of the disk will have a) A non-zero radial acceleration and a non-zero tangential acceleration b) Zero radial acceleration and a zero tangential acceleration c) Zero radial acceleration and a non-zero tangential acceleration d) A non-zero radial acceleration and a zero tangential acceleration
a) A non-zero radial acceleration and a non-zero tangential acceleration
In Example 12.3 (p. 299), suppose the triangular wedge was taken off the axle and tossed up in the air so that it's rotating. About what point would the triangular wedge rotate? a) About a point that lies within the widget, in the area bounded by the plastic rods b) About a point that lies on one of the plastic rods c) About the 300 g mass d) About the 150 g mass e) About the 250 g mass
a) About a point that lies within the widget, in the area bounded by the plastic rods
In Example 11.5 (p. 273), define the system to be the bullet + block. Of the following choices, when is the momentum conserved for this system? Choose all that apply. a) At the moment when the bullet impacts the block b) While the bullet and block are swinging upwards c) None of the above
a) At the moment when the bullet impacts the block
http://phet.colorado.edu/sims/collision-lab/collision-lab_en.html begin to play with the simulation. Once you are familiar with the program, click "Reset All" and "More Data". Set ball 1 to have a mass of 1 kg, position of 1 m and velocity of 1m/s. Set ball 2 to have a mass of 2 kg, position of 2 m and velocity of 0 m/s. Now set the slider to an elasticity of 100% (bouncy) and run the simulation. What do you observe to happen after the collision? a) Ball 1 (light ball) had half the speed of ball 2 (heavy ball) but ball 1's velocity was negative. b) Ball 1 (light ball) had half the speed of ball 2 (heavy ball) and both velocities were positive. c) Ball 1 (light ball) had twice the speed of ball 2 (heavy ball) but ball 1's velocity was negative. d) Ball 1 (light ball) had twice the speed of ball 2 (heavy ball) and both velocities were positive.
a) Ball 1 (light ball) had half the speed of ball 2 (heavy ball) but ball 1's velocity was negative.
In Stop to Think 4.5 (p.96), look at the graph shown for choice b. Which way is the particle moving around the circle during 0-2 s and then 2-6 seconds? a) CW then CCW b) CCW the entire time c) CCW then CW d) CW the entire time
a) CW then CCW
Suppose a car's velocity over time is described by the velocity-vs-time graph in "Stop to Think 2.6" (p. 56). How would you find the instantaneous acceleration of the car at point A? a) Find the slope of the curve in the velocity-vs-time graph at point A b) Divide the car's velocity at point A by the time of point A c) Find the area under the velocity curve between t=0s and the time of point A
a) Find the slope of the curve in the velocity-vs-time graph at point A
http://phet.colorado.edu/sims/collision-lab/collision-lab_en.html Now hit "Reset All" and set all the values to be the same as in question 1, but set the slider to an elasticity of 0% (sticky). What do you observe? a) The balls move together with a final speed that is 1/3 the initial speed of ball 1. b) The balls move together with a final speed that is 1/2 the initial speed of ball 1. c) The balls move together with a final speed that is twice the initial speed of ball 1. d) The balls move together with a final speed that is three times the initial speed of ball 1.
a) The balls move together with a final speed that is 1/3 the initial speed of ball 1.
In Example 12.1 (p. 297), if a third ball was placed on the rod a x=10cm, how would the center of mass of the system change? a) The center of mass position would stay the same b) The answer depends on the mass of the third ball c) The center of mass position would move to the right d) The center of mass position would move to the left
a) The center of mass position would stay the same
In Figure Q7.13 (p. 176), suppose the blocks can be connected by either a heavyweight rope or a lightweight rope. Which rope will approximately have the same tension at both of its ends? a) The lightweight rope b) Both ropes will have the same tension at both of its ends c) The heavyweight rope
a) The lightweight rope
In Figure 6.13 (p. 141), suppose a small child is sitting on top of the box. Which statement below is true? a) The magnitude of the kinetic friction would increase because the upward force that the floor exerts on the box increases b) The magnitude of the kinetic friction would stay the same because the mass of the box did not change c) The magnitude of the kinetic friction would stay the same because the woman's pushing force did not change d) The magnitude of the kinetic friction would increase because the coefficient of static friction increases
a) The magnitude of the kinetic friction would increase because the upward force that the floor exerts on the box increases
For an object that's in static equilibrium which of the following statements must be true? Check all that apply. a) The net torque acting on the object must equal zero b) Friction cannot exert a torque on the object c) The net torque on the object does not have to be zero if the net force on the object is zero d) The net force on the object does not have to be zero if the net torque on the object is zero
a) The net torque acting on the object must equal zero
In Example 3.5 (p. 73), if the rabbit ran at 40 degrees north of east instead of 40 degrees north of west, which is a true statement about how its velocity components would change? a) The sign of v(sub)x would change b) The sign of v(sub)y would change c) v(sub)x would decrease in magnitude d) v(sub)y would decrease in magnitude
a) The sign of v(sub)x would change
In Challenge Example 11.11 (p. 283), if the mass of the steel ball and the paperweight were the same (say 200 g), what would happen to both objects after they collide and the collision is perfectly elastic? a) The steel ball would stop its motion and the paperweight would travel to the right b) The steel ball would reverse its motion (travel to the left) and the paperweight would not move. c) The steel ball would keep moving in the rightward direction and the paperweight would travel to the right d) The steel ball would reverse its motion (travel to the left) and the paperweight would travel to the right.
a) The steel ball would stop its motion and the paperweight would travel to the right
In Example 8.2 (p. 185), suppose the dad spun the child faster around the same circle. In that case, what would be true about the tension? a) The tension in the rope would need to be bigger. b) It would be impossible to spin him faster without changing the radius. c) The tension in the rope would need to be smaller.
a) The tension in the rope would need to be bigger.
In Example 13.1 (p. 344), U1 is the gravitational potential energy before the Earth starts to move and U2 is the gravitational potential energy right when the Earth crashes into the Sun. Notice that both U1 and U2 are negative numbers. Which of the following statements are true regarding the change in the gravitational potential energy, U2-U1? a) U2-U1 is negative because gravitational potential energy is being transformed into kinetic energy b) U2-U1 is positive because the final kinetic energy is negative c) U2-U1 is zero because the system is isolated d) None of the reasonings above are correct
a) U2-U1 is negative because gravitational potential energy is being transformed into kinetic energy
Which of the following would increase the magnitude of the angular acceleration for the Stop To Think 12.5 image (d) on p. 308, assuming the balls are connected by a thin, rigid, massless rod and it rotates about an axle through its center of mass. Check all that apply. a) Increasing the force acting on the left ball from 1 N to 3 N. (The direction of the force is unchanged). b) Increasing the force acting on the left ball from 1 N to 3 N (The direction of the force is unchanged). AND Increasing the force acting on the right ball from 1 N to 3 N (The direction of the force is unchanged). c) Changing the direction of the force acting on the left ball so that it instead points directly at the right ball. (The magnitude of the force is unchanged). d) Changing the direction of the force acting on the left ball so that it instead points upwards. (The magnitude of the force is unchanged).
a) and b)
In Example 12.4 (p. 301), suppose the rod stays on the wall in the same position, but the hinge is moved to be at the center of mass position of the rod. The rod is then held out horizontally and released. How do the energies of the system change after the rod is released? Check all that apply. a) The change in the system's gravitational potential energy would be zero b) The change in the system's gravitational potential energy is positive c) The change in the system's gravitational potential energy is negative d) The change in the system's kinetic energy would zero e) The change in the system's kinetic energy is positive f) The change in the system's Kinetic energy is negative
a) and d)
Which of the following statements are true of absolute temperature? Check all that apply. a) Absolute temperature is a measure of the motions of molecules in a gas. b) At absolute zero temperature, there would be no motion of molecules in a gas. c) Absolute temperature can be measured with a constant-volume gas thermometer. d) Absolute temperature is related to the thermal energy in a system.
a) b) c) and d)
Is it possible for an object's instantaneous velocity and instantaneous acceleration to be of opposite sign at some instant of time? a) yes b) no c) Need more information
a) yes
In Stop to Think 13.4 (p. 346), five pairs of masses are shown. For which pair does the rightmost mass experience the greatest gravitational force? The numbers give the relative masses and distances. a-e
b)
In Example 10.5 (p. 240), the bottom left image in Figure 10.12 shows a block at rest against a compressed spring. At this moment, how much potential energy is stored in the spring? a) .12 J b) 0.051 J c) 6.1 J d) 0.78 J
b) 0.051 J
A bicycle tire is rolling on a flat, paved path. It's center of mass moves at a constant translational velocity v. The point at the bottom of the rolling tire (the point that is in contact with the ground) is traveling at what translational velocity? a) 0 m/s b) 1/2 v c) 2v d) v
b) 1/2 v
In Example 9.9 (p. 221), if the spring was instead pulled back 40 cm, what would be the launch speed of the cube? a) 2.8 m/s b) 10.2 m/s c) 8.4 m/s d) 6.1 m/s
b) 10.2 m/s
In Challenge Example 11.9 (p. 280), after the explosion, suppose that the m1 fragment shot directly north at 12 m/s and the m3 fragment shot directly south at 9 m/s. What would be the x-component of the velocity of the m2 fragment after the explosion? a) 0 m/s b) 6.67 m/s c) -6.67 m/s d) 3.33 m/s e) -3.33 m/s
b) 6.67 m/s
In Example 8.2 (p. 185), why does the cart travel in a circle at a constant speed? a) Because the cart experiences a net force toward the child's father. This net force is due to the force of circular motion on the cart. b) Because the cart experiences a net force toward the child's father. This net force is due to the force exerted by the rope on the cart. c) Because the cart experiences a net force away from the child's father. This net force is due to the force exerted by the rope on the cart. d) Because the cart experiences a net force away from the child's father. This net force is due to the force of circular motion on the cart. e) None of the above. The cart is in uniform circular motion and therefore experiences no net force because its speed stays constant.
b) Because the cart experiences a net force toward the child's father. This net force is due to the force exerted by the rope on the cart.
In Example 10.3 (p. 237), if the origin of the system was displaced 10 m in the upwards direction (5 m above the top of the hill), how would the change in Christine's potential energy be affected when she travels from the top of the hill to the bottom of the hill? a) Her change in potential energy would increase b) Her change in potential energy would stay the same c) Her change in potential energy would decrease
b) Her change in potential energy would stay the same
In Example 4.15 (p. 101), suppose a 52 cm diameter blade was attached to the motor shaft instead of the 76 cm diameter blade. If the fan blade experienced the same angular acceleration, what would happen to the magnitude of the tangential acceleration at the tip of the blade during the first few seconds? a) It would be larger with the 52 cm blade b) It would be smaller with the 52 cm blade c) It would not change
b) It would be smaller with the 52 cm blade
In Example 4.4 (p.86), which statement is true when the car is in free fall? a) Its velocity in the x-direction changes during the free fall b) Its velocity in the x-direction stays constant during the free fall c) Its velocity in the y-direction stays constant during the free fall d) Its acceleration changes during the free fall
b) Its velocity in the x-direction stays constant during the free fall
You are a passenger in a car heading to campus and it stops suddenly. If you aren't wearing a seat belt, you could hit the windshield. In that case, was there a force pushing you forward (toward the windshield)? a) Yes b) No
b) No
One of your classmates, Kevin, is trying to calculate the acceleration due to gravity at the top of Mt. Everest. Looking at an equation sheet, he sees that the acceleration due to gravity is g = (G*M)/r^2. For G, he plugs in the gravitational constant. For M, he plugs in the mass of the Earth. For r, Kevin plugs in the elevation (the height above sea level) of Mt. Everest. Will Kevin arrive at the right answer for g at the top of Mt Everest? a) Yes b) No, his answer will be larger than the correct answer c) No, his answer will be smaller than the correct answer
b) No, his answer will be larger than the correct answer
In Stop to Think 11.1 (p. 265), if the cart came to a stop after running into the wall, how would the impulse delivered to the cart change? a) The impulse delivered to the cart would increase in magnitude b) The impulse delivered to the cart would decrease in magnitude c) The impulse delivered to the cart would be the same
b) The impulse delivered to the cart would decrease in magnitude
In Example 7.9 (p. 174), how do the magnitudes of the accelerations for the furniture and the safe compare to each other? a) The magnitude of the furniture's acceleration is greater than the magnitude of the safe's acceleration b) The magnitude of the furniture's acceleration is the same as the magnitude of the safe's acceleration c) The magnitude of the furniture's acceleration is less than the magnitude of the safe's acceleration
b) The magnitude of the furniture's acceleration is the same as the magnitude of the safe's acceleration
In Example 7.8 (p. 173), how does the magnitude of the tension acting on the set change from when the rope was tied backstage to when the stagehand is being hoisted into the loft? a) The magnitude of the tension increased b) The magnitude of the tension decreased c) The magnitude of the tension is the same for both cases
b) The magnitude of the tension decreased
In Example 10.1 (p. 234), if the pebble was instead launched at a 45 degree angle above the horizontal, how would the total mechanical energy of the system change compared to when the pebble was launched directly upwards? a) The total mechanical energy of the system would increase b) The total mechanical energy of the system would stay the same c) The total mechanical energy of the system would decrease
b) The total mechanical energy of the system would stay the same
In Example 12.2 (p. 298), suppose you wanted to calculate the center of mass of the rod using Equation 12.5. What coordinate system must you use for your calculation? a) A coordinate system that has an origin located at the left end of the rod. b) This calculation is independent of the coordinate system you choose. c) A coordinate system that has an origin located at the middle of the rod. d) A coordinate system that has an origin located at the right end of the rod.
b) This calculation is independent of the coordinate system you choose.
In Stop to Think 7.4 (p. 170), consider the 50 kg block hanging by from a ceiling by a rope (Rope 1). Where does the the tension in Rope 1 exist? a) Only at both of the ends b) Throughout the entire rope c) Only at the end attached to the 50 kg block d) Only at the end attached to the ceiling
b) Throughout the entire rope
Suppose the truck that's transporting the box In Example 6.10 (p. 150) is driving at a constant speed and then brakes and slows at a constant acceleration. While coming to a stop, the driver looks in the rear-view mirror and notices that the box is not slipping. In what direction is the frictional force acting on the box? a) Toward the front of the car b) Toward the back of the car c) There is no frictional force acting on the box
b) Toward the back of the car
You are a passenger in a car and you're not wearing your seat belt. While traveling at a constant speed, the car makes a sharp left turn and you collide with the right-hand door. Which is the correct analysis of the situation. a) Before and after the collision, a force pushes you into the door. b) When you collide with the door, the door exerts a normal force on you. c) A and B are both correct. d) None of the above.
b) When you collide with the door, the door exerts a normal force on you.
As a skier goes down a frictionless slope with a constant inclination, her acceleration is a) changing b) constant (but not zero) c) zero
b) constant (but not zero)
In Example 9.6 (p. 217), if the skier was gliding down the slope at a constant speed, how much work would be done by friction on the skier? a) 0 J b) 5960 J c) -5960 J d) 33780 J e) -33780 J
c) -5960 J
In Example 9.2 (p. 214), if you instead carried the suitcase by the handle so that the suitcase was hanging directly at your side, how much work would you do on the suitcase as you carried it forward at a constant walking speed? a) 1400 J b) 700 J c) 0 J d) -700 J e) -1400 J
c) 0 J
In Figure 9.24 (p. 223), if the tension in the rope is 50 N and the block moves at a constant speed of 3.0 m/s, how much power is the being supplied by the hand pulling the rope? a) 0 W b) 200 W c) 150 W d) 100 W e) 50 W
c) 150 W
In Figure 7.11 (p.165), Earth and the ball form an action/reaction pair. Is F(Earth on Ball) the action force or the reaction force? a) Action Force b) Reaction Force c) An action force is not distinguishable from the reaction force
c) An action force is not distinguishable from the reaction force
Consider vector C from "Stop to Think 3.3" (p. 72). Suppose you wanted to perform a "decomposition" of vector C. What would you do? a) Break it apart into scalars b) break it into any number of smaller vectors that add up to vector C c) Break it into two vectors that are parallel to the axes; these vectors add up to vector C d) Place it at the origin
c) Break it into two vectors that are parallel to the axes; these vectors add up to vector C
A bobsledder pushes her sled across horizontal snow to get it going, then jumps in. After she jumps in, the sled gradually slows to a halt. What forces act on the sled just after she's jumped in? a) Gravity, normal force, kinetic friction, and the force of the push. b) Gravity and normal force. c) Gravity, normal force, and kinetic friction. d) Gravity and the force of the push. e) Gravity and kinetic friction.
c) Gravity, normal force, and kinetic friction.
In Figure 4.21 (p. 92/93), a particle is undergoing uniform circular motion. For the particle, which of the following quantities are zero? I. Angular velocity II. Radial Acceleration III. Tangential Acceleration a) I only b) II only c) III only d) I and III e) I, II, and III
c) III only
In Figure 6.16 (p. 144), a filing cabinet is in the back of a dump truck. The truck's bed is tilted at an angle but the filing cabinet is not moving. Your classmate Kevin tells you that the magnitude of the static friction must be μ s n, where μ s is the coefficient of static friction between the truck's bed and the cabinet, and n is the normal force on the cabinet. Do you agree with Kevin? a) Yes, the static friction force must equal μ(sub)s n b) No, the static friction force must be greater than μ(sub)s n c) No, the static friction force could be less than μ(sub)s n
c) No, the static friction force could be less than μ(sub)s n
If the Moon were to suddenly come to rest so that it is no longer revolving around the Earth, but everything else remained the same, what would happen to the Moon? a) The Moon would remain at rest b) The Moon would start accelerating toward the earth with an acceleration more than 9.8 m/s2 c) The Moon would start accelerating toward the earth with an acceleration less than 9.8 m/s2 d) The Moon would start accelerating toward the earth with an acceleration of 9.8 m/s2 e) The Moon would start traveling toward the Earth at a constant speed
c) The Moon would start accelerating toward the earth with an acceleration less than 9.8 m/s2
The slope of an angular velocity vs time graph yields: a) The change in angular position b) The linear velocity c) The angular acceleration d) The angular momentum
c) The angular acceleration
A ball is in motion. At some point in its motion, its instantaneous acceleration vector is perpendicular to its velocity vector. At this point in its motion, which statement is true? a) The ball speeds up without changing directions b) The ball speeds up and changes direction c) The ball changes direction without changing its speed d) The ball slows down without changing direction e) The ball slows down and changes direction
c) The ball changes direction without changing its speed
In Stop to Think 7.3 (p. 168), if the mass of block B was larger than the mass of block A, how would the force that block A exerts on block B compare to the force that block B exerts on block A? a) The force that block A exerts on block B is greater in magnitude than the force that block B exerts on block A. b) The force that block A exerts on block B is less in magnitude than the force that block B exerts on block A. c) The force that block A exerts on block B is the same in magnitude as the force that block B exerts on block A. d) Only the Hand is exerting a force in this example.
c) The force that block A exerts on block B is the same in magnitude as the force that block B exerts on block A.
In Example 11.1 (p. 265), suppose the bat hit the ball in such a way that the ball experienced the same overall change in velocity, but the contact time with the bat was 12 ms instead. How would the impulse delivered to the ball change? In other words, how would the area under the force curve in Figure 11.7 change? a) The impulse delivered to the ball would increase in magnitude b) The impulse delivered to the ball would decrease in magnitude c) The impulse delivered to the ball would stay the same
c) The impulse delivered to the ball would stay the same
Referring to Figure 1.6 (p. 6), suppose you chose a different coordinate system to analyze the sled's motion. This new coordinate system has an origin at the top of the hill where the sled started its motion. How will the magnitude of the sled's displacement from t=3s to t=4s be affected? a) The magnitude of the sled's displacement increases b) The magnitude of the sled's displacement decreases c) The magnitude of sled's displacement remains the same
c) The magnitude of sled's displacement remains the same
Suppose you drop a book. As the book is falling to the ground, which of the following statements is true? a) The magnitude of the force that the Earth exerts on the book is larger than the magnitude of the force that the book exerts on the Earth b) Because the book is in free fall, there is no force between the Earth and book. c) The magnitude of the force that the Earth exerts on the book is the same as the magnitude of the force that the book exerts on the Earth d) The magnitude of the force that the Earth exerts on the book is smaller than the magnitude of the force that the book exerts on the Earth
c) The magnitude of the force that the Earth exerts on the book is the same as the magnitude of the force that the book exerts on the Earth
In Example 12.5 (p. 302), how would the moment of inertia of the rod change if the pivot point were at x = L/2 instead? a) The moment of inertia of the rod would increase b) The moment of inertia of the rod would not change c) The moment of inertia of the rod would decrease
c) The moment of inertia of the rod would decrease
https://www.youtube.com/watch?v=xJBGfPfE4fQ and watch a 45 second clip from 1:30 -2:15 (the first 90 seconds should be review, after 2:15, it describes cross products, which we will learn about at a later time). What is the dot product of a vector with itself? a) 0 b) The magnitude of itself c) The square of itself
c) The square of itself
Referring to Figure 1.19 (p. 17), when the student is traveling between 300m-500m, which of the following statements are correct? a) The student's velocity and acceleration vectors point in the same direction b) The student's velocity and acceleration vectors point in opposite directions c) The student's acceleration vector is the zero vector
c) The student's acceleration vector is the zero vector
In Example 5.4 (p. 124), suppose that the elevator was accelerating downward. Compared to when the elevator is accelerating upwards, how will the magnitudes of the forces in the free-body diagram change? a) The tension would reduce, but still be greater in magnitude than the gravitational force b) The tension would reduce and be equal in magnitude to the gravitational force c) The tension would reduce and be less in magnitude than the gravitational force
c) The tension would reduce and be less in magnitude than the gravitational force
Referring to Figure 1.12 (p. 10), compare the magnitudes of the average accelerations for Hare and the Tortoise. a) The Hare has a larger average acceleration than the tortoise b) The tortoise has a larger acceleration than the hare c) The tortoise and the hare have the same average acceleration
c) The tortoise and the hare have the same average acceleration
Suppose you are driving a car and you're approaching a curve in the road. This curve is banked; however, this banked curve is covered in ice, making the road approximately frictionless. Will you be able to make the turn without slipping up or down the bank? a) No. To make the turn, you need friction between the car's tires and the road b) Yes, but only at speeds between 0 m/s and a critical speed c) Yes, but only at one critical speed d) Yes. During the turn, a normal force is acting on the car, so you can make the turn at any speed
c) Yes, but only at one critical speed
In Figure 12.29 (p. 310), a block is attached to a non-slipping rope draped across a pulley. Which of the following is true? Check all that apply. a) The block's acceleration must have the same magnitude as the rim's angular acceleration b) The block's acceleration must have the same magnitude as the rim's centripetal acceleration. c) The block's velocity must have the same magnitude as the rim's tangential velocity d) The block's velocity must have the same magnitude as the rim's angular velocity e) The block's acceleration must have the same magnitude as the rim's tangential acceleration
c) and e)
Look at Stop to Think 12.4 choice (c ) on p. 305. If you doubled the applied force (instead of 2N, you made it 4 N) but kept everything else the same, the magnitude of torque exerted on that rod would a) increase b) decrease c) remain the same
c) remain the same
In Example 3.1 (p. 67), suppose you chose a coordinate system such that the East points in the positive x-direction and North points in the positive y-direction. What is the y-component the bird's net displacement? a) 100 m b) 50 m c) 43 m d) 36 m d) 65 m
d) 36 m
Suppose you toss a ball up in the air. As the ball is traveling through the air, forces act on the ball. In the absence of air resistance, what are the agent(s) of the force(s) acting on the ball? Pay attention to the distinction between the force itself and the agent of the force when answering this question. a) Gravity b) Agent Smith c) The ball d) Earth
d) Earth
Referring to Figure 4.17 (p. 90/91), in Bill's reference frame, how is Carlos moving? Assume left is the negative x direction and right is the positive x direction for each reference frame. a) He is moving to the right at 5 m/s b) He is moving to the left at 5 m/s c) He is moving to the right at 10 m/s d) He is moving to the left at 10 m/s e) He is moving to the right at 15 m/s f) He is moving to the left at 15 m/s
d) He is moving to the left at 10 m/s
In Figure 13.16 (p. 347), what is the total energy of the orbiting satellite? (Assume your system is the satellite + the Earth.) a) It Depends on the speed of the orbiting satellite. b) More than 0 J (a positive value) c) 0 J d) Less than 0 J (a negative value)
d) Less than 0 J (a negative value)
The average acceleration vector must point in the same direction as which of the following vectors? a) The displacement vector b) The average velocity vector c) The position vector d) None of the above
d) None of the above
In Example 7.2 (p. 163), how many action/reaction pairs of forces are acting on the truck? a) One action/reaction pair: Static friction and the tension b) One action/reaction pair: The normal force and the gravitational force c) Two action/reaction pairs: Static friction/tension and normal force/gravitational force d) None. The two forces of action/reaction pairs act on different objects.
d) None. The two forces of action/reaction pairs act on different objects.
In Example 11.3 (p. 270), when Bob jumps on the cart, what kind of collision is this? a) Inelastic, but not perfectly inelastic b) Rigid c) Elastic d) Perfectly inelastic
d) Perfectly inelastic
The vector cross product A → × B → is maximized when the vectors A → and B → are: a) Parallel b) Are 180 degrees with respect to each other c) At 45 degrees with respect to each other d) Perpendicular
d) Perpendicular
Take a look at the ball in free fall in the third frame from the left in Figure 10.18 (p. 245). What is true about the ball's state of equilibrium? a) Stable Equilibrium b) Unstable Equilibrium c) Neutral Equilibrium d) The ball is not in equilibrium
d) The ball is not in equilibrium
In Figure 5.2 (p. 112), two forces are applied to a box. In which direction will the box accelerate? a) The box does not accelerate b) Not enough information c) The box will accelerate in the opposite direction of the net force d) The box will accelerate in the direction of the net force e) The box will accelerate in the direction of the larger force
d) The box will accelerate in the direction of the net force
In Example 4.15 (p. 101), suppose a 52 cm diameter blade was attached to the motor shaft instead of the 76 cm diameter blade. What would happen to the magnitudes of the radial and tangential accelerations at the tip of the blade? a) The radial acceleration and tangential acceleration would both increase b) The radial acceleration would increase and the tangential acceleration would decrease c) The radial acceleration would decrease and the tangential acceleration would increase d) The radial acceleration and tangential acceleration would both decrease
d) The radial acceleration and tangential acceleration would both decrease
In Example 5.6 (p. 125), a tow rope pulls a skier up a snow-covered hill. Which statement is true? a) The skier is in static equilibrium b) The skier is not in equilibrium c) The skier is in unstable equilibrium d) The skier is in dynamic equilibrium
d) The skier is in dynamic equilibrium
In Example 13.2 (p. 345), if instead the rocket launched from the Earth at 12,000 m/s, what would happen once it reached a distance infinitely far away from Earth. a) When this rocket is an infinite distance away from Earth, the rocket would have no kinetic energy and no gravitational potential energy b) The rocket would not be able to reach deep space at this launch speed c) When this rocket is an infinite distance away from Earth, the rocket would have some kinetic energy and some gravitational potential energy d) When this rocket is an infinite distance away from Earth,, the rocket would have some kinetic energy and no gravitational potential energy
d) When this rocket is an infinite distance away from Earth,, the rocket would have some kinetic energy and no gravitational potential energy
Is a net force acting on the object represented in Figure Q1.5 (in the upper middle part of page 28)? If so, in what direction? a) no b) You cannot determine if a net force is acting on the object c) Yes. In the downward direction d) Yes, in the upward direction
d) Yes, in the upward direction
Which of the following examples involves energy transformations within the system? a) When a car is traveling at a constant speed and applies the brakes (System: Car) b) When a brick is placed on top of a spring (System: Brick and Spring) c) When a roller coaster cart is dragged up a hill by a motor-powered chain (System: The roller coaster cart) d) both A and B e) A, B, and C
d) both A and B
The slope of the line tangent to the curve in a position vs. time graph for a particle's motion gives a) the particle's speed b) the particle's acceleration c) the particle's average velocity d) he particle's instantaneous velocity e) not covered in the reading assignment
d) he particle's instantaneous velocity
In Example 11.3 (p. 270), suppose we instead defined our system to be just Bob. Compared to when the system was defined to be Bob+cart, how would things be different for the collision of Bob with the cart? a) The momentum of the system is no longer conserved b) The system's change in momentum is different c) The impulse on the system is different d) B and C are correct e) A, B, and C are correct
e) A, B, and C are correct
You and your classmates are asked to consider what would happen to you if Earth's gravity was suddenly turned off. One of your classmates says that you would be pushed off Earth into space by the centrifugal force exerted on you by Earth's rotation. Do you agree with your classmate? a) Yes b) No. A centrifugal force is not acting on you. Since there is no identifiable agent for centrifugal force, centrifugal force is not a real force. c) No. The centrifugal force caused by Earth's rotation would cause you to keep rotating with the Earth d) No. The reason you would fly off into space is because of your inertia. Without gravity, there would be no net force toward the center of the Earth to keep rotating with the earth. Hence, you would start moving in a straight line and travel into space. e) Both B and D are both correct responses to your classmate.
e) Both B and D are both correct responses to your classmate.
In Stop To Think 12.7 (p.324) in what direction is the angular momentum of the two bucket system? a) Angular momentum is a scalar; it has no direction b) It is pointing out of the page c) It is pointing into the page d) It is pointing towards the bottom of the page e) It is pointing towards the top of the page
e) It is pointing towards the top of the page
What happens to the maximum height and maximum speed if you change the mass of the skater from heavy to light? a) The lighter skater had a larger maximum speed and had more total energy than the heavier skater b) The lighter skater had a smaller maximum speed and had less total energy than the heavier skater c) The lighter skater had a larger maximum speed and had the same total energy as heavier skater d) The lighter skater had the same maximum speed and had more total energy than the heavier skater e) The lighter skater had the same maximum speed and had less total energy than the heavier skater f) The lighter skater had the same maximum speed and had the same total energy as the heavier skater
e) The lighter skater had the same maximum speed and had less total energy than the heavier skater
Suppose you were dragging a table across a rough floor. In this case, the potential energy for friction depends on which quantity or quantities? (Choose all that apply) a) The total distance the table travels b) The magnitude of the table's displacement c) The coefficient of friction between the table and the floor d) The magnitude of the normal force that the floor exerts on the table e) There is no potential energy for frictional forces
e) There is no potential energy for frictional forces
What are the SI units for arc length?
meters