PHYS1100: Final Exam Practice Questions

In the figure, four point masses are placed as shown. The x and y coordinates of the center of mass are closest to A) (2.3 m, 2.8 m) B) (2.2 m, 2.6 m) C) (2.2 m, 2.7 m) D) (2.3 m, 2.6 m) E) (2.3 m, 2.7 m)

A) (2.3 m, 2.8 m)

A 3.50 kg book slides along a rough horizontal surface. Initially the book is traveling at 2.25 m/s. At some later point, the book is traveling at 1.87 m/s. What is the work done on the book? A) -2.74 J B) -7.40 J C) -8.62 J D) -5.52 J E) -4.14J

A) -2.74 J

A child throws a rock with an initial velocity of 2.15 m/s at 30.0° above the horizontal. If air resistance is negligible, how long does it take for the rock to reach the maximum height of its trajectory? A) 0.110 s B) 0.194 s C) 0.215 s D) 0.303 s E) 0.479 s

A) 0.110 s

Standing waves if frequency 57.0 Hz are produced on a string that has mass per unit length 0.0160 kg/m. With what tension must the string be stretched between two supports if adjacent nodes in the standing wave are to be 0.710 meters apart? A) 105 N B) 195 N C) 245 N D) 307 N

A) 105 N

A man stands on the roof of a building of height 14.5 m and throws a rock with a velocity of magnitude 33.2 m/s at an angle of 32.10 above the horizontal. You can ignore air resistance. What is the horizontal distance from the base of the building to the point where the rock strikes the ground? A) 121 m B) 133 m C) 154 m D) 162 m E) 169 m

A) 121 m

A machinist turns the power on to a grinding wheel, which is at rest at time t=0.0. The wheel accelerates uniformly for 10 s and reaches the operating angular velocity of 25 rad/s The wheel is run at that angular velocity for 37 s and then power is shut off. The wheel decelerates uniformly at 1.5 rad/s2 until the wheel stops. In this situation, the time interval of angular deceleration (slowing down) is closest to A) 17 s. B) 15 s. C) 19 s. D) 21 s. E) 23 s.

A) 17 s.

A force Fx is applied to a 3.0 kg box parallel to the x-axis as it moves in a straight line. The force varies with the x-coordinate of the box as shown in the figure. Initially, at x = 0 m, the box is traveling at a speed of 1.0 m/s. What is the speed of the box at x = 5.0 m? A) 2.4 m/s B) 1.7 m/s C) 3.5 m/s D) 4.5 m/s E) 1.4 m/s

A) 2.4 m/s

Three masses lie in the z = 0 plane of a Cartesian coordinate system. The figure at right shows the x- and y-coordinates of masses m = 10 kg, M1 = 30 kg, and M2 = 50 kg. The masses are spherical and have radii that are much smaller than the distances separating one another. They can all therefore be treated as point masses. Find the magnitude of the net gravitational force FG that M1 and M2 exert on m. The gravitational constant G = 6.67 × 10−11 Nm2⁄kg2. A) 2.59 × 10−9N B) 1.27 × 10−8N C) 3.55 × 10−9N D) 8.89 × 10−10N

A) 2.59 × 10−9N

If 𝐵 = −2.0𝑖̂ − 6.0𝑗̂ + 2.0𝑘 and 𝐶 = −2.0𝑖̂ − 2.0𝑗̂ − 3.0𝑘, which of the following numbers is closest to the magnitude of 𝐶 × 𝐵? A) 25 B) 21 C) 17 D) 13 E) 91

A) 25

A standing wave is oscillating at 700 Hz on a string, as shown in the figure. What is the speed of traveling waves on this string? A) 280 m/s B) 410 m/s C) 210 m/s D) 140 m/s

A) 280 m/s

A 600. kg car is going around a banked curve with a radius of 110. m at a speed of 24.5 m/s. What is the appropriate banking angle, θ, so that the car stays on its path without the assistance of friction? A) 29.1° B) 13.5° C) 33.8° D) 56.2° E) 60.9°

A) 29.1°

A 60.0-kg person rides in an elevator while standing on a scale. The scale reads 400 N. The acceleration of the elevator is closest to A) 3.13 m/s2 downward B) 3.13 m/s2 upward C) zero D) 6.67 m/s2 downward E) 6.67 m/s2 upward

A) 3.13 m/s2 downward

A 1.2-kg spring-activated toy bomb slides on a smooth surface along the x-axis with a speed of 0.50 m/s. At the origin 0, the bomb explodes into two fragments. Fragment 1 has a mass of 0.40 kg and a speed of 0.90 m/s along the negative y-axis. In the figure, the angle θ, made by the velocity vector of fragment 2 and the x-axis, is closest to A) 31°. B) 37°. C) 38°. D) 53°. E) 59°.

A) 31°.

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) 4.2 m/s B) 2.7 m/s C) 5.1 m/s D) 6.1 m/s E) 7.3 m/s

A) 4.2 m/s

A stationary listener (observer O) is between two stereo speakers(1 and 2) as shown in the figure.The speakers are identical in all ways, including the frequencyand phase at which they emitsound waves. Speaker 1 is at rest and emits a steady tone at frequency f1 = 400 Hz.Speaker 2 also emits a steady tone at the same frequency (f2 = 400 Hz), but is moving toward O at a speed 𝑣2. The tones from the two speakers generate beats at O's location. If O hears 50.0 beats in 10.0 seconds, and the speed of sound in air is 344 m/s, 𝑣2 is A) 4.25 m/s. B) 38.2 m/s. C) 2.66 m/s. D) 9.33 m/s.

A) 4.25 m/s.

A 20.0 N box rests on a 50.0 N box on a frictionlesshorizontal floor. When a horizontal 15.0 N pull to the right isexerted on the lower box (see figure), both boxes movetogether. The coefficient of kinetic friction between the twoboxes is 0.600 and the coefficient of static friction betweenthe two boxes is 0.800. Find the magnitude and direction of the net force on the upper box. A) 4.29 N to the right. B) 4.29 N to the left. C) 8.58 N to the right. D) 8.58 N to the left. E) 0.00 N and no direction

A) 4.29 N to the right.

While spinning down from 500.0 rpm to rest, a solid uniform disk does 5.1 kJ of work. If the radius of the disk is 1.2 m, what is its mass? (𝐼𝑑𝑖𝑠𝑘 = 1 𝑀𝑅2) A) 5.2 kg B) 4.4 kg C) 6.0 kg D) 6.8 kg E)8.9 kg

A) 5.2 kg

A metal disk rotates on an axis through its center (I = 0.2 kg m2) with angular velocity -3.3 radians/s and a torque equal to +1.6 Nm is applied to it by pushing on its outer rim. What is the resulting angular acceleration of the disk? A) -4.0 radians/s2 B) +4.0 radians/s2 C) -8.0 radians/s2 D) +8.0 radians/s2 E) none of the above

D) +8.0 radians/s2

A 0.2-kg ball moving at 2.0 m/s perpendicular to a wall rebounds from the wall at 1.5 m/s. The impulse given to the ball is: A) zero B) 3.5 N-s away from wall C) 3.5 N.s toward wall D) 0.7 N-s away from wall E) 0.7 N-s toward wall

D) 0.7 N-s away from wall

A block of mass 0.5 kg attached to an ideal spring with a spring constant of 80 N/m oscillates on a horizontal frictionless surface. At a time, where the spring is 4.0 cm longer than its equilibrium length, the speed of the block is 0.50 m/s.What is the greatest speed of the block? A) 0.23 m/s B) 0.32 m/s C) 0.55 m/s D) 0.71 m/s E) 0.93 m/s

D) 0.71 m/s

Four identical particles, each with mass m = 2.0 kg, are arranged in the x, y plane as shown. They are connected by 4 identical sticks of length a = 1.0 m but negligible mass to form a rigid body.What is the rotational inertia of this body about the y-axis? A) 4.0 kg m2 B) 4.8 kg m2 C) 9.6 kg m2 D) 12 kg m2 E) None of these

D) 12 kg m2

Given the following three vectors: 𝑎⃑ = −9.3m𝑖̂ + 2.7m𝑗̂ +5.2m𝑘 𝑏 = −2.0m𝑖̂− 4.0m𝑗̂ +2.0m𝑘 𝑐⃑= 2.0m𝑖̂ + 3.0m𝑗̂ +1.0m𝑘 What is the result of ⃑𝑎⃑⃑ ∙ (𝑏 + 𝑐⃑ ) ? A) 4.3 m2 B) 7.3 m2 C) 10.5 m2 D) 12.9 m2

D) 12.9 m2

The tension in a string with a linear density of 0.0010 kg/m is 0.40 N. A 100 Hz sinusoidal wave on this string has a wavelength of: A) 0.05 cm B) 2.0 cm C) 5.0 cm D) 20 cm E) 100 cm

D) 20 cm

A spring-loaded dart gun is used to shoot a dart straight up into the air, and the dart reaches a maximum height of 24 meters above its point of release. The same dart is shot up a second time from the same gun, but this time the spring is compressed only half as far (compared to the first shot). How far up does the dart go this time? (Neglect friction and assume the spring is ideal and massless.) A) 6.0 m B) 12 m C) 3.0 m D) 48 m E) 7.8 m

A) 6.0 m

A small model car with mass m = 0.800 kg travels at constant speed v on the inside of a track that is a vertical circle with radius r = 5.00 m (see the figure). If the normal force exerted on the car by the track when it is at the bottom of the track (point A) is NA = 21.7 N, the normal force NB acting on the car when it is at the top of the track (point B) is A) 6.02 N. B) 13.8 N. C) 1.84 N. D) 21.7 N. E) 15.6 N.

A) 6.02 N.

A flywheel is initially rotating at 20 rad/s and has a constant angular acceleration. After 9.0 s it has rotated through 450 rad. What is its angular acceleration? A) 6.7 rad/s2 B) 7.5 rad/s2 C) 8.6 rad/s2 D) 9.9 rad/s2 E) 11 rad/s2

A) 6.7 rad/s2

Two stationary tuning forks (350 Hz and 352 Hz) are struck simultaneously. The resulting sound is observed to: A) Beat with a frequency of 2 beats/s. B) Beat with a frequency of 351 beats/s. C) Be loud but not beat. D) Be Doppler shifted by 2 Hz. E) Have a frequency of 702 Hz.

A) Beat with a frequency of 2 beats/s.

Four traveling waves are described by the following equations, where all quantities are measured in SI units and y represents the displacement. I: y = 0.12 cos(3x - 21t) II: y = 0.15 sin(6x + 42t) III: y = 0.13 cos(6x + 21t) IV: y = -0.27 sin(3x - 42t) Which of these waves have the same period? A) I and III, and also II and IV B) I and IV, and also II and III C) I and II, and also III and IV D) All of them have the same period.

A) I and III, and also II and IV

When a man on a frictionless rotating stool extends his arms horizontally, his rotational kinetic energy: A) Must decrease. B) Must increase. C) Must remain the same. D) May increase or decrease depending on his initial angular velocity

A) Must decrease.

A ball is thrown down from a tall building and falls for 6 seconds before it hits the ground. Consider how far the ball falls in its first 3 seconds of free fall (from t = 0 s to t = 3 s) compared to how far it falls in its next 3 seconds (from t = 3 s to t = 6 s). Assume that there's no air resistance. A) The ball falls farther in the second 3-second interval than it does in the first interval. B) The ball falls the same distance in both 3-second intervals. C) The ball falls a smaller distance in the second 3-second interval than it does in the first interval. D) To answer this question we need the value of the initial velocity. E) To answer this question we need the mass of the ball.

A) The ball falls farther in the second 3-second interval than it does in the first interval.

An object is moving forward with a constant velocity. Which statement about this object MUST be true? A) The net force on the object is zero. B) The net force on the object is in the forward direction. C) No forces are acting on the object. D) The acceleration of the object is in the forward direction. E) The acceleration of the object is in the backward direction.

A) The net force on the object is zero.

Consider a traveling wave described by the formula, 𝑦(𝑥, 𝑡) = 𝑦 𝑚 𝑠𝑖𝑛 (𝑘𝑥 − 𝜔𝑡). Which one of the following statements about the wave described in the formula is correct? A) The wave is traveling in the +x direction B) The wave is traveling in the −x direction C) The wave is oscillating but not traveling D) The wave is traveling but not oscillating

A) The wave is traveling in the +x direction

A ball on the end of a string is rotating withconstant speed in a horizontal plane. When the ball is moving North it is located to the East of the pivot point. At that time the angular velocity of the ball points in what direction? A) Up B) Down C) East D) West E) North

A) Up

An object is moving to the right, and experiencing a net force that is directed to the right. The magnitude of the force is decreasing with time but the direction is still to the right. The speed of the object is A) increasing. B) decreasing. C) constant in time. D) zero. E) To answer this we need more information.

A) increasing.

A 310 g air track cart is traveling at 1.25 m/s and a 260 g cart traveling in the opposite direction at 1.33 m/s. What is the speed of the center of mass of the two carts? A) 2.80 m/s B) 0.0732 m/s C) 0.131 m/s D) 1.47 m/s E) 1.29 m/s

B) 0.0732 m/s

In the figure at right, m1 = 20. kg, m2 = 36 kg, and a = 53.1o. What is the coefficient of kinetic friction between the block of mass m1 and the incline surface if the hanging block m2 is to descend 12.0 m in the first 3.00 s after the system is released from rest? A) 0.25 B) 0.40 C) 0.54 D) 0.61 E) 0.78

B) 0.40

What is the difference between 103.5 and 102.24 written with the correct number of significant figures? A) 1 B) 1.3 C) 1.26 D) 1.260 E) 1.2600

B) 1.3

A 5.00 kg object is moving at 12.0 m/s on a frictionless floor when it collides with and sticks to another 5.00 kg object that is initially at rest. See the figure below. After the collision, how high above the floor will the combined objects go? A) 0.54 m B) 1.84 m C) 2.78 m D) 3.56 m E) 4.12 m

B) 1.84 m

A package is dropped from a helicopter moving upward at 15 m/s and it takes 16 s just 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) 1300 m D) 1500 m E) 1700m

B) 1000 m

A simple harmonic oscillator has an amplitude of 2.00 cm and a maximum speed of 13.0 cm/s. What is its speed when the displacement is 1.00 cm? A) 9.24 cm/s B) 11.3 cm/s C) 14.2 cm/s D) 15.0 cm/s

B) 11.3 cm/s

A 50.0 kg object rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.300 and the coefficient of kinetic friction is 0.200. What is the friction force on the object if a horizontal 140 N push is applied to it? A) 98.0 N B) 140. N C) 147 N D) 245 N E) 490 N

B) 140. N

A 6.0-kg particle moves to the right at 4.0 m/s as shown. In reference to point O on the right, what is the magnitude of the particle's angular momentum? A) 24 kg m2/s B) 144 kg m2/s C) 249 kg m2/s D) 288 kg m2/s E) 0

B) 144 kg m2/s

A ball is thrown horizontally from the top of a 20 m high hill. It strikes the ground at an angle of 45o as shown in the figure. With what speed was the ball thrown? Neglect air resistance. A) 13.6 m/s B) 19.8 m/s C) 27.7 m/s D) 31.4 m/s E) 35.1 m/s

B) 19.8 m/s

A constant force of 8.0 N is exerted for a duration of 4.0 s on an object of mass 16 kg initially at rest. The change in speed of this object will be: A) 0.5 m/s B) 2.0 m/s C) 4.0 m/s D) 8.0 m/s E) 32 m/s

B) 2.0 m/s

The figure given below depicts the oscillation of an oscillator. The mathematical expression of the oscillation is x(t) = xmcos(ωt+φ). What is the phase constant, φ, of the oscillation? A) 1.4 radians B) 2.1 radians C) 3.2 radians D) 3.7 radians

B) 2.1 radians

For a simple harmonic motion (SHM) the displacement x of the particle from the origin is given as a function of time by x(t) = xm cos (t + ), where the xm is the maximum displacement in units of meter, is the angular frequency in units of rad/s, and is the phase constant. If the SHM is described as x(t) = 0.5 cos (20 t + ), the magnitude of the maximum acceleration is A) 10 m/s2 B) 200 m/s2 C) 100 m/s2 D) 20 m/s2

B) 200 m/s2

Two small identical speakers are connected (in phase) to the same source. The speakers are 3 m apart and at ear level. An observer stands at X, 4 m in front of one speaker as shown. If the amplitudes are not changed, the sound the observer hears will be least intense if the wavelength is: A) 1m B) 2m C) 3m D) 4m

B) 2m

A 12.0 kg box resting on a horizontal frictionless surface is attached to a 5.00 kg weight by a thin wire that passes over a frictionless pulley. See figure. The pulley has the shape of a uniform solid disk of mass M = 2.00 kg. The rotational inertia of a disk is 1⁄2 MR2. After the system is released, what is the tension acting on the 5.0 kg mass? A) 3.95 N B) 35.4 N C) 24.0 N D) 19.5 N E) 127 N

B) 35.4 N

A rock is thrown vertically upward from ground level at time t = 0. At t = 1.9 s it passes the top of a tall tower, and 1.0 s later it reaches its maximum height. What is the height of the tower? A) 21.8 m B) 36.3 m C) 39.9 m D) 49.9 m E) 62.1 m

B) 36.3 m

In the figure shown three boxes are connected by cords, one of which wraps over a pulley having negligible friction on its axle and negligible mass. The masses are mA = 32 kg, mB = 44 kg, and mC = 14 kg. After the assembly is released from rest, what is the tension in the cord connecting B and C? A) 31.6 N B) 48.8 N C) 72.8 N D) 137 N E) 431 N

B) 48.8 N

A church pipe organ consists of several pipes that generate sound waves. Pipe A of the organ is open at both ends and has a length L. Pipe B of the organ is identical to A, except that it has one open end and one closed end. When A is played in its third harmonic and B is played in its fundamental mode, beats having a frequency fb = 86 Hz are generated. Given that the speed of sound when the beats are created is v = 344 m/s, the length of pipes A and B is A) 10 m. B) 5.0 m. C) 3.5 m. D) 2.0 m.

B) 5.0 m.

Consider a cylinder of radius 0.10 m and length 0.20 m. Its rotational inertia, round the cylinder axis is 0.020 kg m2. A string is wound around the cylinder and pulled with a force of 1.0 N perpendicular to the cylinder's axis. What is the angular acceleration of the cylinder ? A) 2.5 rad/s2 B) 5.0 rad/s2 C) 10 rad/s2 D) 15 rad/s2 E) 20 rad/s2

B) 5.0 rad/s2

A child on a sled starts from rest at the top of a 30.0° slope. If the trip to the bottom takes 15.0 s, how long is the slope? Assume that frictional forces may be neglected. A) 293 m B) 551 m C) 795 m D) 1130 m E) 1470m

B) 551 m

The four forces shown have the same strength. Which force produces the least torque about the hinge? A) Force 𝐹1 B) Force 𝐹2 C) Force 𝐹3 D) Force 𝐹4 E) Either𝐹1 or𝐹4

B) Force 𝐹2

Four identical point masses are attached to each corner of a massless and rigid square frame as in the figure. A and B are axes on the surface of page pointing to the directions in the figure. The axis C is perpendicular to the page and goes through the center of the left bottom mass. IA, IB and IC are the rotational inertia about the axis A, B, and C. Which of the following is correct? A) IA >IB >IC B) IC > IA > IB C) IB > IA > IC D) IA >IC >IB E) IA = IB = IC

B) IC > IA > IB

The center of mass of a system of particles has a constant velocity if: A) The forces exerted by the particles on each other sum to zero. B) The external forces acting on particles of the system sum to zero. C) The velocity of the center is initially zero. D) The particles are distributed symmetrically around the center of mass. E) The center of mass is at the geometric center of the system.

B) The external forces acting on particles of the system sum to zero.

Three objects, a disk (𝐼 = 1 𝑀𝑅2), a solid sphere (𝐼 = 2 𝑀𝑅2), and a hoop (𝐼 = 𝑀𝑅2), all with the same mass and radius, are at rest on top of an inclined plane. They simultaneously begin to roll down the incline plane without slipping. Which object will arrive first at the bottom? A) The hoop will arrive first at the bottom. B) The sphere will arrive first at the bottom. C) The disc will arrive first at the bottom. D) They will arrive at the bottom at the same time.

B) The sphere will arrive first at the bottom.

A box of mass m is pressed against (but is not attached to) an ideal spring of force constant k and negligible mass, compressing the spring a distance x. After it is released, the box slides up a frictionless incline as shown in the figure and eventually stops. If we repeat this experiment but instead compress the spring a distance of 2x A) the box will go up the incline twice as high as before. B) just as it moves free of the spring, the box will be traveling twice as fast as before. C) just as it moves free of the spring, the box will be traveling four times as fast as before. D) just as it moves free of the spring, the box will have twice as much kinetic energy as before. E) just before it is released, the box has twice as much elastic potential energy as before.

B) just as it moves free of the spring, the box will be traveling twice as fast as before.

A 70 kg man is floating at rest near his spaceship. He throws a 1.5 kg wrench away from the ship at a speed of 10 m/s in order to move himself toward it. With what speed does he move toward the ship? A) 4.62 m/s B) 1.46 m/s C) 0.21 m/s D) 0.13 m/s E) None of the above

C) 0.21 m/s

A solid flat disk of mass M = 4.0 kg and radius R = 0.20 m is rotating about an axis passing through its center as shown in the right figure. The moment of inertia of the disc about an axis passing through center of mass is 1⁄2 MR2. What is the moment of inertia of the disc about an axis passing through its edge? A) 0.08 kg m2 B) 0.16 kg m2 C) 0.24 kg m2 D) 0.08 kg m2 E) None of the above.

C) 0.24 kg m2

In the figure, an object of mass m moves a distance of 8.0 m on a rough horizontal surface. During this motion the speed changes from 9.0 m/s to 2.0 m/s. What is the coefficient of kinetic friction between the object and the rough surface? A) 0.30 B) 0.37 C) 0.49 D) 0.54 E) 0.61

C) 0.49

A uniform wooden disk of mass M = 4.0 kg and radius R = 0.50 m is on africtionless horizontal surface and rotates with an angular speed ωd = 2.5 rad/sabout a vertical axle through its center. The figure at right shows the disk andits sense of rotation when viewed from above. A very small ball of putty withmass m = 0.50 kg slides along the surface toward the disk at speed |⃗𝒗⃗ | = 3.0m/s, directed along a line tangent to the disk's edge (i.e., perpendicular to theradial line shown in the figure). The putty ball sticks to the edge of the disk, and afterward they rotate as a single unit. Given that the moment of inertia of the disk about its central axle is I = 1⁄2 MR2, the angular speed of the disk+putty ball system ωd+m after they stick together is A) 0.50 rad/s. B) 2.0 rad/s. C) 0.80 rad/s. D) 1.6 rad/s.

C) 0.80 rad/s.

A uniform piece of string with a length L = 5.00 m and mass m = 0.0100 kg is held taut by an unknown tension FT applied at both ends of the string. The string is plucked and transverse waves obeying the relation 𝑦(𝑥, 𝑡) = (8.50 mm) sin[(180 rad⁄m)𝑥 − (4900 rad/s)𝑡] are generated in the string. The tension FT is A) 0.675 N B) 3.84 N C) 1.48 N D) 0.0544 N.

C) 1.48 N

An object at rest at the origin of an xy coordinate system explodes into three pieces. Just after the explosion, one piece, of mass m, moves with velocity (-32 m/s)𝑖̂ and a second piece, also of mass m, moves with velocity (-32 m/s) 𝑗̂. The third piece has mass 3m. Just after the explosion, what is the magnitude of the velocity of the third piece? A) 5.70 m/s B) 10.6 m/s C) 15.0 m/s D) 21.2 m/s E) 25.0 m/s

C) 15.0 m/s

A projectile returns to its original height 4.08 s after being launched, during which time it travels 76.2 m horizontally. If air resistance can be neglected, what was the projectile's initial speed? A) 18.7 m/s B) 21.6 m/s C) 27.4 m/s D) 31.2 m/s E) 37.5 m/s

C) 27.4 m/s

Blocks A and B are moving toward each other on a frictionless horizontal surface. Block A has a mass of 2.0 kg and a velocity of +50 m/s 𝑖̂, while B has a mass of 4.0 kg and a velocity of -25 m/s 𝑖̂. They collide and stick together. The kinetic energy lost during the collision is: A) 0 J B) 1250 J C) 3750 J D) 5000 J E) 5600 J

C) 3750 J

A 0.500 kg steel ball is dropped from an initial height yi = +2.00 m above a solid metal floor. The ball rebounds vertically upward, stopping at a final height yf = +1.60 m above the floor. The vertical impulse that the floor exerts on the ball is A) 8.37 Ns. B) 0.330 Ns. C) 5.93 Ns. D) 2.09 Ns. E) 4.20 Ns.

C) 5.93 Ns.

In the figure, a very light rope is wrapped around a wheel of radius R = 2.0 meters and does not slip. The wheel is mounted with frictionless bearings on an axle through its center. A block of mass 14 kg is suspended from the end of the rope. When the system is released from rest it is observed that the block descends 10 meters in 2.0 seconds. What is the moment of inertia of the wheel? A) 15 kg • m2 B) 28 kg • m 2 C) 54 kg • m2 D) 65 kg • m2 E) 72kg • m2

C) 54 kg • m2

A small asteroid of mass m = 1.50 × 1013 kg collides with the planet Mars. The speed ofthe asteroid when it was very far from the planet was 3.60 × 103 m/s. Given that Mars has a mass M = 6.42 × 1023 kg and a radius R = 3.39 × 106 m, and that the gravitational constant G = 6.67 × 10−11 Nm2⁄kg2, the speed at which the asteroid impacts the Martian surface is A) 8.63 × 103 m/s. B) 4.29 × 103 m/s. C) 6.18 × 103 m/s. D) 7.15 × 103 m/s.

C) 6.18 × 103 m/s.

A nonuniform beam of mass M = 20.0 kg and length L = 3.00 m is suspended from a ceiling at an angle of 40° below the horizontal. The pole is attached to the ceiling by a hinge at one end and a support rope attached to the other end. The center of gravity of the beam (located at the "" in the figure) is a distance lcog = 1.00 m from the pivot. The tension in the support rope is A) 196 N. B) 50.0 N. C) 65.3 N. D) 42.0 N.

C) 65.3 N.

In a collision between two objects having unequal masses, how does the magnitude of an impulse imparted to the lighter object by the heavier one compare with the magnitude of an impulse imparted to the heavier object by the lighter one? A) The lighter object receives the larger magnitude of an impulse. B) The heavier object receives the larger magnitude of an impulse. C) Both objects receive the same impulse. D) The answer depends on the ratio of the masses. E) The answer depends on the ratio of the speeds.

C) Both objects receive the same impulse.

Let F1 be the magnitude of the gravitational force exerted on the Sun by Earth and F2 be the magnitude of the force exerted on Earth by the Sun. Then: A) F1 is much greater than F2. B) F1 is slightly greater than F2. C) F1 is equal to F2. D) F1 is slightly less than F2. E) F1 is much less than F2.

C) F1 is equal to F2.

Consider a wave of the form, 𝑦(𝑥, 𝑡) = 1.0 𝑠𝑖𝑛(10𝑥) cos(2.0𝑡), where t is the time. A) This wave is traveling in the +x direction. B) This wave is traveling in the −x direction. C) This wave is oscillating but not traveling. D) This wave is traveling but not oscillating.

C) This wave is oscillating but not traveling.

The mass of the Moon is 1/81 of the mass of the Earth. Compared to the gravitational force that the earth exerts on the Moon, the gravitational force that the Moon exerts on the Earth is A) 812 times greater. B) 81 times greater. C) equally strong. D) (1/81)2 as great.

C) equally strong.

What are the units of the standard deviation of measured acceleration values? A) No units B) m/s C) m/s2 D) N E) kg

C) m/s2

If you ignore air resistance, the horizontal component of the velocity of an object experiencing projectile motion A) decreases as it moves upward and increases as it moves downward. B) increases as it moves upward and decreases as it moves downward. C) stays constant the entire time it is in flight. D) decreases the entire time it is in flight. E) increases the entire time it is in flight.

C) stays constant the entire time it is in flight.

A uniform solid sphere (𝐼 = 2 𝑀𝑅2) is rolling without slipping along a horizontal surface with a 5 speed of 5.50 m/s when it starts up a ramp that makes an angle of 25.0° with the horizontal. What is the speed of the sphere after it has rolled 3.00 m up the ramp, measured along the surface of the ramp? A) 8.02 m/s B) 1.91 m/s C) 2.16 m/s D) 3.53 m/s

D) 3.53 m/s

A planet has a mass of 0.0558 times the mass of Earth and a radius of0.381 times the radius of Earth. The acceleration of a body falling near the surface of the planet is about: A) 0.21 m/s2 B) 1.4 m/s2 C) 2.8 m/s2 D) 3.8 m/s2 E) 7.5 m/s2

D) 3.8 m/s2

A mass m = 5.0 kg is suspended by a rope at the end of a uniform horizontal pole of length L = 8.0 m and mass M = 10 kg. The pole is attached at one end to a vertical wall by a hinge. A cable affixed to the wall and connected to the pole a distance d = 4.0 m from the wall also helps to support the pole. The cable makes an angle of 60° with respect to the wall. The normal force that the wall exerts on the pole is A) 200 N. B) 470 N. C) 160 N. D) 340 N.

D) 340 N.

A stationary source S generates circular outgoing waves on a lake. The wave speed is 5.0 m/s and the crest-to-crest distance is 2.0 m. A person in a motor boat heads directly toward S at a speed of 3.0 m/s. To this person, the frequency of the waves is: A) 1.0 Hz B) 1.5 Hz C) 2.0 Hz D) 4.0 Hz E) 8.0 Hz

D) 4.0 Hz

The following four forces act on a 4.00 kg object: F1 = -300 N 𝑖̂, 2 = 700 N 𝑗̂, 3 = 500 N 𝑖̂, 4 = -600 N 𝑗̂. What is the magnitude of the acceleration of the object and the angle between the acceleration and the positive x-axis? A) 55.9 m/s2, 63.4° B) 75.0 m/s2, 63.4° C) 75.0m/s2, 26.6° D) 55.9 m/s2, 26.6° E) 300m/s2,26.6°

D) 55.9 m/s2, 26.6°

A 3-kg block, attached to a spring, executes simple harmonic motion according to x = 2cos(50t) where x is in meters and t is in seconds. The spring constant of the spring is: A) 100 N/m B) 1000 N/m C) 4500 N/m D) 7500 N/m E) 9200 N/m

D) 7500 N/m

During volleyball practice a volleyball is tossed over a net, starting from a height of 1.5 meters above the ground. After reaching the top of its trajectory it returns to its original height as it falls. How does the motion of the ball at the top of its trajectory compare to its motion as it passes its original height? Ignore air resistance. A) The ball's acceleration and velocity are both different at the two moments. B) The ball's acceleration and velocity are the same at the two moments. C) The ball's velocity is the same at the two moments, but its acceleration is different. D) The ball's acceleration is the same at the two moments, but its velocity is different. E) The ball's velocity at the top is zero but its velocity is not zero as it passes its original height.

D) The ball's acceleration is the same at the two moments, but its velocity is different.

You throw a ball upward. When the ball is moving up, what can you conclude about the gravitational force exerted on the ball? A) The gravitational force does positive work on the ball and decreases its kinetic energy. B) The gravitational force does negative work on the ball and increases its kinetic energy. C) The gravitational force does positive work on the ball and increases its kinetic energy. D) The gravitational force does negative work on the ball and decreases its kinetic energy. E) The gravitational force does no work on the ball and decreases its kinetic energy.

D) The gravitational force does negative work on the ball and decreases its kinetic energy.

A car is moving due South. What is the direction of the torque on the wheels while it slows down? A) North B) South C) East D) West

D) West

The figure shows a particle moving at a constant velocity 𝑣. There are five points a, b, c, d, and e with their x and ycoordinates labeled. Rank the points according to the magnitude of the angular momentum of the particle measured about each point, greatest first. A) b > c > d > e > a B) e > c > b > d > a C) e > b > d > a > c D) b > d = c > a = e

D) b > d = c > a = e

A shell explodes into two fragments, one fragment 25 times heavier than the other. If any gas from the explosion has negligible mass, then A) the momentum change of the lighter fragment is 25 times as great as the momentum change of the heavier fragment. B) the momentum change of the heavier fragment is 25 times as great as the momentum change of the lighter fragment. C) the kinetic energy change of the heavier fragment is 25 times as great as the kinetic energy change of the lighter fragment. D) the kinetic energy change of the lighter fragment is 25 times as great as the kinetic energy change of the heavier fragment.

D) the kinetic energy change of the lighter fragment is 25 times as great as the kinetic energy change of the heavier fragment.

Shock waves occur when A) the frequency of the waves is the resonant frequency of the system. B) the amplitude of waves exceeds the critical shock value. C) two waves from different sources collide with each other. D) the wave source is traveling at a speed greater than the wave speed.

D) the wave source is traveling at a speed greater than the wave speed.

A disk of radius R = 1.5 m and mass M = 20 kg rotates around a fixed axis passing through its center. The graph shows the angular momentum l of the disk along the rotation axis as a function of time t. The net external torque acting on the disk at t = 2.0 s is A) 60 Nm. B) 15 Nm. C) −15 Nm. D) −60 Nm.

D) −60 Nm.

A uniform solid cylindrical log (𝐼 = 1 𝑀𝑅2) begins rolling without slipping down a ramp that rises 2 28.0° above the horizontal. After it has rolled 4.20 m along the ramp, what is the magnitude of the linear acceleration of its center of mass? A) 9.80 m/s2 B) 4.60 m/s2 C) 3.29 m/s2 D) 3.07 m/s2

D. 3.07 m/s2

Two uniform disks rotate independently around a common axis. One of the disks rotates in one direction at 1.00 rad/s and the other rotates in the opposite direction at 2.00 rad/s. Each flywheel has the same rotational inertia of 50.0 kg•m2. Calculate the magnitude of the net angular momentum of the system. A) 20 kg•m2/s B) 30kg•m2/s C) 40kg•m2/s D) 50 kg•m2/s

D. 50 kg•m2/s

At t = 8.0 s, what is the x-coordinate of the object? A) -5.0 m B) -3.5 m C) 0.0 m D) +3.5 m E) +5.0 m

E) +5.0 m

A traveling wave on a string is described by y = 7.9 sin[2π(t/0.87 + x/90)]where x and y are in meters and t is in seconds. Determine the wave velocity, including direction (+ if the wave is moving in the +x direction, - if it is moving in the -x direction). A) -0.0097 m/s B) 16 m/s C) -16 m/s D) 100 m/s E) -100 m/s

E) -100 m/s

An object moves along the x-axis. The graph below shows the velocity of the object as a function of time. At time t = 0.0 s, the object is located at x = 1.5 m. 5. What is the acceleration of the object at t = 2.0 s? A) -0.30 m/s2 B) -0.67 m/s2 C) 0.00 m/s2 D) 0.30 m/s2 E) 0.67 m/s2

E) 0.67 m/s2

A block attached to a spring oscillates in simple harmonic motion along the x axis. The limits of its motion are x = 10 cm and x = 50 cm and it goes from one of these extremes to the other in a time of 0.25 s. What are its amplitude and frequency? A) 40 cm, 2 Hz B) 20 cm, 4 Hz C) 40 cm, 2 Hz D) 25 cm, 4 Hz E) 20 cm, 2 Hz

E) 20 cm, 2 Hz

A 32-N force, parallel to the incline, is required to push a certain crate at constant velocity up a frictionless incline that is O = 30° above the horizontal (see figure).What is the mass of the crate? A) 2.5 kg B) 3.3 kg C) 3.8 kg D) 5.7 kg E) 6.5 kg

E) 6.5 kg

Consider an object speeding up as it moves along a level surface. Which of the following is a Newton's third law pair? A) The force of friction exerted on the object by the surface and the air resistance exerted on the object by the air. B) The force of friction exerted on the object by the surface and the normal force exerted on the object by the surface. C) The force of gravity exerted on the object by the Earth and the air resistance exerted on the object by the air. D) The force of gravity exerted on the object by the Earth and the normal force exerted on the object by the surface. E) The normal force exerted on the object by the surface and the normal force exerted on the surface by the object.

E) The normal force exerted on the object by the surface and the normal force exerted on the surface by the object.

When an object travels in a circular path at constant speed, which one of the following statements is wrong? A) The direction of the object's acceleration is directed toward the center of the circular path. B) The object's velocity and acceleration are perpendicular. C) The object's velocity is changing. D) The object's acceleration is changing. E) The object's acceleration is zero.

E) The object's acceleration is zero.

A playground merry-go-round has a radius R and a rotational inertia I. When the merry-go-round is at rest, a child with mass m runs with speed v along a line tangent to the rim and jumps on. The angular velocity of the merry-go-round is then: A) mv/I B) v/R C) mRv/I D) 2mRv/I E) mRv/(mR2 + I)

E) mRv/(mR2 + I)

An object moves on level, frictionless surface. It is attached by a rope to a vertical post set in the surface. The object moves around the post at constant speed in a circle of radius R. If the rope breaks, A) the object will keep moving in a circle. B) the object will move on a curved path, but not a circle. C) the object will follow a curved path for a while, then move in a straight line. D) the object will move in a straight line for a while, then follow a curved path for a while. E) the object will move in a straight line.

E) the object will move in a straight line.