4) Vector = and vector = What is vector = +? A) B) C) D) E)

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1 1) Suppose that an object is moving with constant nonzero acceleration. Which of the following is an accurate statement concerning its motion? A) In equal times its speed changes by equal amounts. B) In equal times its velocity changes by equal amounts. C) In equal times it moves equal distances. D) A graph of its position as a function of time has a constant slope. E) A graph of its velocity as a function of time is a horizontal line. 2) The velocity of an object as a function of time is given by v(t) = 2.00 m/s + (3.00 m/s) t - (1.0 m/s2) t2. Determine the instantaneous acceleration of the object at time t = 5.00 s. A) m/s2 B) m/s2 C) 2.00 m/s2 D) 0.00 m/s2 E) m/s2 3) A car accelerates from 10.0 m/s to 30.0 m/s at a rate of 3.00 m/s2. How far does the car travel while accelerating? A) 80.0 m B) 133 m C) 226 m D) 399 m 4) Vector = and vector = What is vector = +? A) B) C) D) E) ) An object has a position given by = [2.0 m + (5.00 m/s)t] + [3.0 m - (2.00 m/s2)t2], where quantities are in SI units. What is the speed of the object at time t = 2.00 s? A) 6.40 m/s B) 9.43 m/s C) 7.00 m/s D) 7.65 m/s E) 13.0 m/s 6) In a shuffleboard game, the puck slides a total of 12 m before coming to rest. If the coefficient

2 of kinetic friction between the puck and the horizontal board is 0.28, what was the initial speed of the puck? A) 8.1 m/s B) 29.0 m/s C) 6.5 m/s D) 7.3 m/s 7) An object weighing 4.00 N falls from rest subject to a frictional drag force given by Fdrag = bv2, where v is the speed of the object and What terminal speed will this object approach? A) 1.78 m/s B) 3.42 m/s C) 1.15 m/s D) 2.25 m/s E) 0.75 m/s 8) A car enters a 300-m radius horizontal curve on a rainy day when the coefficient of static friction between its tires and the road is What is the maximum speed at which the car can travel around this curve without sliding? A) 29.6 m/s B) 33.1 m/s C) 24.8 m/s D) 42.0 m/s E) 37.9 m/s 9) In an INELASTIC collision between two objects A) the momentum of each object is conserved. B) the kinetic energy of each object is conserved. C) the momentum of the system is conserved but the kinetic energy of the system is not conserved. D) both the momentum and the kinetic energy of the system are conserved. E) the kinetic energy of the system is conserved, but the momentum of the system is not conserved. 10) How much energy is needed to change the speed of a 1600 kg sport utility vehicle from 15.0 m/s to 40.0 m/s? A) 1.10 MJ B) 10.0 kj C) 20.0 kj D) 40.0 kj E) MJ

3 11) Determine the scalar product of = and = A) B) C) 12 D) 60 E) undefined 12) The work performed as a function of time for a process is given by W = at 3 where a = 2.4 J/s 3. What is the instantaneous power output at t = 3.7 s? A) 99 W B) 69 W C) 138 W D) 207 W??13) A solid, uniform sphere of mass 2.0 kg and radius 1.7 m rolls from rest without slipping down an inclined plane of height 7.0 m. What is the angular velocity of the sphere at the bottom of the inclined plane? A) 5.8 rad/s B) 9.9 rad/s C) 11 rad/s D) 7.0 rad/s 14) When can we be certain that the average velocity of an object is always equal to its instantaneous velocity? A) always B) never C) only when the velocity is constant D) only when the acceleration is constant E) only when the acceleration is changing at a constant rate

4 15 The figure shows the graph of the position x as a function of time for an object moving in the straight line (the x-axis). Which of the following graphs best describes the velocity along the x- axis as a function of time for this object? A) B) C) D) E)

5 16) Which one of the following graphs could possibly represent the vertical position as a function of time for an object in free fall? A) B) C) D)

6 E) 17) The position of an object as a function of time is given by where c = 60 m/s and d = 7.0 m. (a) Find the instantaneous acceleration at t =2.4 s. (b) Find the average acceleration over the first 2.4 seconds. Answer: (a) 44 m/s2 (b) 18 m/s2 Var: 1 18) A runner maintains constant acceleration after starting from rest as she runs a distance of 60.0 m. The runner's speed at the end of the 60.0 m is 9.00 m/s. How much time did it take the runner to complete the 60.0 m distance? A) 6.67 s B) 15.0 s C) 9.80 s D) 10.2 s E) 13.3 s

7 19) A package is dropped from a helicopter moving upward at 15 m/s. If it takes 16.0 s before the package strikes the ground, how high above the ground was the package when it was released if air resistance is negligible? A) 810 m B) 1000 m C) 1200 m D) 1500 m 21) An object has a position given by = [2.0 m + (3.00 m/s)t] + [3.0 m - (2.00 m/s2)t2], where all quantities are in SI units. What is the magnitude of the acceleration of the object at time t = 2.00 s? A) 1.00 m/s2 B) 0.00 m/s2 C) m/s2 D) 4.00 m/s2 E) 2.00 m/s2 22) A hockey puck slides off the edge of a table with an initial velocity of 28.0 m/s. and experiences no air resistance. The height of the tabletop above the ground is 2.00 m. What is the angle below the horizontal of the velocity of the puck just before it hits the ground? A) 77.2 B) 72.6 C) 12.8 D) 12.6 E) ) A box slides down a frictionless plane inclined at an angle θ above the horizontal. The gravitational force on the box is directed A) parallel to the plane in the same direction as the movement of the box. B) parallel to the plane in the opposite direction as the movement of the box. C) perpendicular to the plane. D) vertically. E) at an angle θ below the inclined plane.

8 24) A 60.0-kg person rides in elevator while standing on a scale. The elevator is traveling downward but slowing down at a rate of 2.00 m/s2. The reading on the scale is closest to A) 589 N. B) 708 N. C) 469 N. D) 120 N. E) 349 N. 25) A 6.0 kg box slides down an inclined plane that makes an angle of 39 with the horizontal. If the coefficient of kinetic friction is 0.19, at what rate does the box accelerate down the slope? A) 4.7 m/s2 B) 5.2 m/s2 C) 5.5 m/s2 D) 6.2 m/s2 26) A 200 g hockey puck is launched up a metal ramp that is inclined at a 30 angle. The coefficients of static and kinetic friction between the hockey puck and the metal ramp are μs = 0.40 and μk = 0.30, respectively. The puck's initial speed is 63 m/s. What vertical height does the puck reach above its starting point? A) 130 m B) 270 m C) 200 m D) 66 m 27) A 250-kg crate is on a rough ramp, inclined at 30 above the horizontal. The coefficient of kinetic friction between the crate and ramp is A horizontal force of 5000 N is applied to the crate, pushing it up the ramp. What is the acceleration of the crate? A) 8.4 m/s2 B) 10 m/s2 C) 12 m/s2 D) 13 m/s2 E) 3.4 m/s2 28) An 80.0-kg object is falling and experiences a drag force due to air resistance. The magnitude of this drag force depends on its speed, v, and obeys the equation What is the terminal speed of this object? A) 6.45 m/s

9 B) 72.2 m/s C) 34.2 m/s D) 12.6 m/s E) 47.3 m/s 29) A string is attached to the rear-view mirror of a car. A ball is hanging at the other end of the string. The car is driving around in a circle, at a constant speed. Which of the following lists gives all of the forces directly acting on the ball? A) tension and gravity B) tension C) tension, gravity, and the centripetal force D) tension, gravity, the centripetal force, and friction 30) A 1000-kg car is slowly picking up speed as it goes around a horizontal curve whose radius is 100 m. The coefficient of static friction between the tires and the road is At what speed will the car begin to skid sideways? A) 9.25 m/s B) 23.6 m/s C) 34.3 m/s D) 35.0 m/s E) 18.5 m/s 31) A small glider is coasting horizontally when suddenly a very heavy piece of cargo falls out of the bottom of the plane. You can neglect air resistance. Just after the cargo has fallen out A) the plane speeds up and the cargo slows down. B) the plane speeds up but the cargo does not change speed. C) neither the cargo nor the plane change speed. D) the cargo slows down but the plane does not change speed. E) both the cargo and the plane speed up. Answer: C 32) A small car has a head-on collision with a large truck. Which of the following statements concerning the magnitude of the average force due to the collision is correct? A) The truck experiences the greater average force. B) The small car experiences the greater average force. C) The small car and the truck experience the same average force. D) It is impossible to tell since the masses are not given. E) It is impossible to tell since the velocities are not given.

10 33) Which of the graphs in the figure illustrates Hooke's Law? A) Graph a B) Graph b C) Graph c D) graph d 34) Is it possible for a system to have negative potential energy? A) Yes, as long as the kinetic energy is positive. B) Yes, as long as the total energy is positive. C) Yes, since the choice of the zero of potential energy is arbitrary. D) No, because the kinetic energy of a system must equal its potential energy. E) No, because this would have no physical meaning. 7) In a perfectly ELASTIC collision between two perfectly rigid objects A) the momentum of each object is conserved. B) the kinetic energy of each object is conserved. C) the momentum of the system is conserved but the kinetic energy of the system is not conserved. D) both the momentum and the kinetic energy of the system are conserved. E) the kinetic energy of the system is conserved, but the momentum of the system is not conserved.

11 35) A force on a particle depends on position such that F(x) = (3.00 N/m 2 )x 2 + (6.00 N/m)x for a particle constrained to move along the x-axis. What work is done by this force on a particle that moves from x = 0.00 m to x = 2.00 m? A) 10.0 J B) 20.0 J C) J D) 24.0 J E) 48.0 J 36) A force F = bx3 acts in the x direction, where the value of b is 3.7 N/m3. How much work is done by this force in moving an object from x = 0.00 m to x = 2.6 m? A) 42 J B) 13 J C) 50 J D) 57 J 37) A kg car is moving at 15 km/h. If a kg truck has 18 times the kinetic energy of the car, how fast is the truck moving? A) 45 km/h B) 63 km/h C) 54 km/h D) 36 km/h 38) Determine the angle between the directions of vector = and vector = A) 26.6 B) 30.0 C) 88.1 D) 117 E) ) The angle between vector = and vector is The scalar product of vectors and is If the x component of vector is positive, what is vector. A) B) C) D) E)

12 40) A traveler pulls on a suitcase strap at an angle 36 above the horizontal. If 908 J of work are done by the strap while moving the suitcase a horizontal distance of 15 m, what is the tension in the strap? A) 75 N B) 61 N C) 85 N D) 92 N 41) The work performed as a function of time for a process is given by W = at 3 where a = 2.4 J/s 3. What is the instantaneous power output at t = 3.7 s? A) 99 W B) 69 W C) 138 W D) 207 W 42) A car on a roller coaster starts at zero speed at an elevation above the ground of 26 m. It coasts down a slope, and then climbs a hill. The top of the hill is at an elevation of 16 m. What is the speed of the car at the top of the hill? Neglect any frictional effects. A) 14 m/s B) 18 m/s C) 10 m/s D) 9.0 m/s E) 6.0 m/s??????? 43) Consider the motion of a 1.00-kg particle that moves with potential energy given by U(x) = (-2.00 J m)/x + (4.00 J m2)/x2. Suppose the particle is moving with a speed of 3.00 m/s when it is located at x = 1.00 m. What is the speed of the object when it is located at x = 5.00 m? A) 2.13 m/s B) 3.00 m/s C) 4.68 m/s D) 3.67 m/s

13 44) A 2.0-kg object is moving without friction along the x-axis. The potential energy curve as a function of position is shown in the figure, and the system is conservative. If the speed of the object at the origin is 4.0 m/s, what will be its speed at 7.0 m along the +x-axis? A) 4.0 m/s B) 4.2 m/s C) 4.4 m/s D) 4.6 m/s E) 9.8 m/s 45) When a rigid body rotates about a fixed axis, all the points in the body have the same A) tangential speed. B) angular acceleration. C) tangential acceleration. D) linear displacement. E) centripetal acceleration. 46) The two rotating systems shown in the figure differ only in that the two identical movable masses are positioned at different distances from the axis of rotation. If you release the hanging blocks simultaneously from rest, and if the ropes do not slip, which block lands first? A) The block at the left lands first. B) The block at the right lands first. C) Both blocks land at the same time.

14 47) Consider a uniform solid sphere of radius R and mass M rolling without slipping. Which form of its kinetic energy is larger, translational or rotational? A) Its translational kinetic energy is larger than its rotational kinetic energy. B) Its rotational kinetic energy is larger than its translational kinetic energy. C) Both forms of energy are equal. D) You need to know the speed of the sphere to tell. 48) The angular acceleration of a wheel is given in rad/s2by 45t 3 11t 4, where t is in seconds. If the wheel starts from rest at t = 0.00 s, when is the next time the wheel is at rest? A) 5.1 s B) 8.4 s C) 6.9 s D) 3.6 s 49) A 95 N force exerted at the end of a 0.50 m long torque wrench gives rise to a torque of What is the angle (assumed to be less than 90 ) between the wrench handle and the direction of the applied force? A) 18 B) 14 C) 22 D) 25??50) A uniform solid disk of radius 1.60 m and mass 2.30 kg rolls without slipping to the bottom of an inclined plane. If the angular velocity of the disk is 5.35 rad/s at the bottom, what is the height of the inclined plane? A) 5.61 m B) 4.21 m C) 4.94 m D) 6.73 m 51) A 5.0-m radius playground merry-go-round with a moment of inertia of 2000 kg m2 is rotating freely with an angular speed of 1.0 rad/s. Two people, each having a mass of 60 kg, are standing right outside the edge of the merry-go-round and step on it with negligible speed. What is the angular speed of the merry-go-round right after the two people have stepped on? A) 0.20 rad/s B) 0.40 rad/s C) 0.60 rad/s D) 0.80 rad/s E) 0.67 rad/s

15 52) A baseball is located at the surface of the earth. Which statements about it are correct? (There may be more than one correct choice.) A) The earth exerts a much greater gravitational force on the ball than the ball exerts on the earth. B) The ball exerts a greater gravitational force on the earth than the earth exerts on the ball. C) The gravitational force on the ball due to the earth is exactly the same as the gravitational force on the earth due to the ball. D) The gravitational force on the ball is independent of the mass of the ball. E) The gravitational force on the ball is independent of the mass of the earth. 53) If the mass of the earth and all objects on it were suddenly doubled, but the size remained the same, the acceleration due to gravity at the surface would become A) 4 times what it now is. B) 2 times what it now is. C) the same as it now is. D) 1/2 of what it now is. E) 1/4 of what it now is. 54) Neptune circles the Sun at a distance of m once every 164 years. Saturn circles the Sun at a distance of 1.43 x 1012 m. What is the orbital period of Saturn? A) 304 y B) 121 y C) 109 h D) 88.6 y E) 29.4 y 55) A mass M is attached to an ideal massless spring. When this system is set in motion, it has a period T. What is the period if the mass is doubled to 2M? A) 2T B) T/2 C) T D) 4T E) T 56) A certain frictionless simple pendulum having a length L and mass M swings with period T. If both L and M are doubled, what is the new period? A) 4T B) 2T C) T D) T E) T/4