Anna's Ultimate Exam Practice Test

(has picture) Two objects having masses m1 and m2 are connected to each other as shown in the figure and are released from rest. There is no friction on the table surface or in the pulley. The masses of the pulley and the string connecting the objects are completely negligible. What must be true about the tension T in the string just after the objects are released? T > m2g T < m2g T = m1g T = m2g T > m1g

incorrect

(has picture)In the figure, a constant external force P = 160 N is applied to a 20.0-kg box, which is on a rough horizontal surface. While the force pushes the box a distance of 8.00 m, the speed changes from 0.500 m/s to 2.60 m/s. The work done by friction during this process is closest to +1110 J +1040 J +1170 J -1040 J -1170 J

-1040 J

The following exact conversion equivalents are given: 1 m = 100 cm, 1 in = 2.54 cm, and 1 ft = 12 in. If a computer screen has an area of 1.27 ft2, this area is closest to 0.0465 m2. 4.65 m2. 0.284 m2. 0.00284 m2. 0.118 m2.

0.118

Satellite Motion: If Earth had twice its present mass but it orbited at the same distance from the sun as it does now, its orbital period would be 3 years. 4 years. 2 years. 6 months. 1 year.

1 year

An 8.0-g bullet is shot into a 4.0-kg block, at rest on a frictionless horizontal surface (see the figure). The bullet remains lodged in the block. The block moves into an ideal massless spring and compresses it by 8.7 cm. The spring constant of the spring is 2400 N/m. The initial velocity of the bullet is closest to 1000 m/s. 1100 m/s. 900 m/s. 1200 m/s. 1300 m/s.

1100 m/s

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. 399 m B. 226 m C. 80 m D. 133 m

133 m

(has picture)Rotational Kinetic Energy: A solid uniform disk of diameter 3.20 m and mass 42 kg rolls without slipping to the bottom of a hill, starting from rest. If the angular speed of the disk is 4.27 rad/s at the bottom, how high did it start on the hill? 3.57 m 3.14 m 2.68 m 4.28 m

2.0

(has picture) A 2.0 g bead slides along a frictionless wire, as shown in the figure. At point A, the bead is moving to the right but with negligible speed.What is the potential energy of the bead at point A? Express your answer with the appropriate units. What is the kinetic energy of the bead at point B? Express your answer with the appropriate units. What is the speed of the bead at point B? Express your answer with the appropriate units. What is the speed of the bead at point C? Express your answer with the appropriate units.

2.0×10−2 j, 2.0×10−2 j, 4.4 m/s, 2.0 m/s

(has picture) Three objects are connected as shown in the figure. The strings and frictionless pulleys have negligible masses, and the coefficient of kinetic friction between the 2.0-kg block and the table is 0.25. What is the acceleration of the 2.0-kg block? 1.7 m/s2 2.5 m/s2 3.2 m/s2 4.0 m/s2

2.5

Projectile Motion: A girl throws a rock horizontally, with a velocity of 10 m/s, from a bridge. It falls 20 m to the water below. How far does the rock travel horizontally before striking the water, assuming negligible air resistance? 20 m 16 m 14 m 24 m

20

Conversion of Units: Express 50 mi/h in units of meters per second. (1 mi = 1609 m) 49 m/s 45 m/s 2.2 m/s 22 m/s

22 m/s

In his youth, Profjohn could throw a baseball at a speed of 25.00 m/s. If he throws the baseball at an angle of 40.0° above the horizontal and the ball leaves his hand 1.00 m above the ground experiencing very negligible air resistance, how long and how far does the ball travel before it hits the ballfield?How long is the ball in flight before it hits the ground? Express your answer with the appropriate "mks" units. How far does the ball travel before it hits the ballfield? Express your answer with the appropriate "mks" units.

3.43s , 65.8 m

Rotational Kinetic Energy: A solid uniform disk of diameter 3.20 m and mass 42 kg rolls without slipping to the bottom of a hill, starting from rest. If the angular speed of the disk is 4.27 rad/s at the bottom, how high did it start on the hill? 3.57 m 3.14 m 2.68 m 4.28 m

3.57 m

Profjohn walks out of the studio to pick up the newspaper and travels 3.90 meters in the x-direction, turns and walks -4.00 meters in the y-direction. What is the angle measured counterclockwise from the +x-axis? 136° 224° 314° 134° 46.0º

314

A block lies on a horizontal frictionless surface. A horizontal force of 100 N is applied to the block giving rise to an acceleration of 3.0 m/s2. Determine the mass of the block. Express your answer with the appropriate units. Calculate the distance the block will travel if the force is applied for 10 s. Express your answer with the appropriate units. Calculate the speed of the block after the force has been applied for 10 s. Express your answer with the appropriate units.

33 kg, 150 m, 30 m/s

Angular Quantities: A chicken is running in a circular path with an angular speed of 1.52 rad/s. How long does it take the chicken to complete one revolution? 4.77 s 2.07 s 118 s 4.13 s 8.26 s

4.13

Profjohn walks out of the studio to pick up the newspaper and travels 3.90 meters in the x-direction, turns and walks -4.00 meters in the y-direction. What is the distance from the door? 7.9 meters 5.6 meters 0.1 meters

5.6

Gravitational Force: What is the gravitational force acting on a 59-kg person due to another 59-kg person standing 2.0 m away? We can model each person as a small sphere. (G = 6.67 × 10-11 N ∙ m2/kg2) 5.8 × 10-8 N 1.2 × 10-7 N 9.8 × 10-10 N 8.5 × 103 N 2.0 × 10-9 N

5.8 × 10-8 N

screenshot number 3 66° below the +x-axis 24° above the +x-axis 24° below the +x-axis 66° above the +x-axis

66 below

Angular Quantities: What is the angular speed, in rad/s, of a flywheel turning at 813.0 rpm? 95.33 rad/s 13.53 rad/s 85.14 rad/s 63.84 rad/s

85.14

A ball is projected upward at time t = 0.0 s, from a point on a roof 90 m above the ground. The ball rises, then falls and strikes the ground. The initial velocity of the ball is 36.2 m/s if air resistance is negligible. The time when the ball strikes the ground is closest to 8.7 s 9.0 s 9.7 s 9.4 s 10 s

9.4

Constant Angular Acceleration: An old LP record that is originally rotating at 33.3 rad/s is given a uniform angular acceleration of 2.15 rad/s2. Through what angle has the record turned when its angular speed reaches 72.0 rad/s? 66.8 rad 948 rad 83.2 rad 697 rad 316 rad

948

Angular and Linear Quantities: A scooter has wheels with a diameter of 120 mm. What is the angular speed of the wheels when the scooter is moving forward at 6.00 m/s? 72.0 rpm 100 rpm 50.0 rpm 955 rpm 47.7 rpm

955

(has picture) The motions of a car and a truck along a straight road are represented by the velocity-time graphs in the figure. The two vehicles are initially alongside each other at time t = 0. At time T, what is true about these two vehicles since time t = 0? A.The truck will have traveled further than the car. B.The truck and the car will have traveled the same distance. C.The car will have traveled further than the truck. D.The car will be traveling faster than the truck.

A

Rotational Kinetic Energy: Consider a uniform hoop of radius R and mass M rolling without slipping. Which is larger, its translational kinetic energy or its rotational kinetic energy? Translational kinetic energy is larger. Rotational kinetic energy is larger. Both are equal. You need to know the speed of the hoop to tell.

Both are equal.

General Questions: A satellite is in orbit around the earth. Which one feels the greater force? the satellite because the earth is so much more massive Earth and the satellite feel exactly the same force. the earth because the satellite has so little mass It depends on the distance of the satellite from Earth.

Earth and the satellite feel exactly the same force.

Gravitational Force: Two small balls, A and B, attract each other gravitationally with a force of magnitude F. If we now double both masses and the separation of the balls, what will now be the magnitude of the attractive force on each one? F 16F F/4 8F 4F

F

Angular and Linear Quantities: Two children, Ahmed and Jacques, ride on a merry-go-round. Ahmed is at a greater distance from the axis of rotation than Jacques. Which of the following are true statements? (There could be more than one correct choice.) Ahmed has a greater tangential speed than Jacques. Jacques has a smaller angular speed than Ahmed. Jacques and Ahmed have the same tangential speed. Jacques and Ahmed have the same angular speed. Jacques has a greater angular speed than Ahmed.

Jacques and Ahmed have the same angular speed.

Banked Curves: Two cars go around a banked curve at the proper speed for the banking angle. One car has tires with excellent traction, while the other car has bald slippery tires. Which of these cars is more likely to slide on the pavement as it goes around the curve? the car with the new tires the car with the bald tires Neither car will slide. It depends on if the pavement is wet or dry.

Neither car will slide.

(has picture) Multiple-Object Accelerating Systems: Two boxes are connected to each other by a string as shown in the figure. The 10-N box slides without friction on the horizontal table surface. The pulley is ideal and the string has negligible mass. What is true about the tension T in the string? T = 30 N T < 30 N T > 30 N T = 10 N T = 20 N

T < 30 N

A box of mass m is pulled with a constant acceleration a along a horizontal frictionless floor by a wire that makes an angle of 15° above the horizontal. If T is the tension in this wire, then T = ma. T > ma. T < ma.

T > ma.

Two objects are thrown from the top of a tall building and experience no appreciable air resistance. One is thrown up, and the other is thrown down, both with the same initial speed. What are their speeds when they hit the street? The one thrown up is traveling faster. The one thrown down is traveling faster. They are traveling at the same speed.

They are traveling at the same speed

(has picture)Two objects, each of weight W, hang vertically by spring scales as shown in the figure. The pulleys and the strings attached to the objects have negligible weight, and there is no appreciable friction in the pulleys. The reading in each scale is more than 2W. less than W. W. more than W, but not quite twice as much. 2W.

W.

An object is moving with constant non-zero acceleration along the +x-axis. A graph of the velocity in the x direction as a function of time for this object is a parabolic curve. a horizontal straight line. a vertical straight line. a straight line making an angle with the time axis.

a straight line making an angle with the time axis.

screenshot 4 choice (a) choice (b) choice (c) choice (d)

choice (b)

While an object is in projectile motion (with upward being positive) with no air resistance A. the vertical component of its velocity remains constant and the vertical component of its acceleration is equal to -g. B.the horizontal component of its velocity remains constant and the horizontal component of its acceleration is equal to -g. c.the vertical component of both its velocity and its acceleration remain constant. d.the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to -g. e.the horizontal component of its velocity remains constant and the vertical component of its acceleration is equal to zero.

d

(has picture)The motion of a particle is described in the velocity versus time graph shown in the figure. We can say that its speed decreases and then increases. increases and then decreases. increases. decreases.

decreases and then increases.

Rotational Kinetic Energy: A disk and a hoop of the same mass and radius are released at the same time at the top of an inclined plane. If both are uniform, which one reaches the bottom of the incline first if there is no slipping? The disk The hoop Both reach the bottom at the same time.

disk

A 1.0-kg block and a 2.0-kg block are pressed together on a horizontal frictionless surface with a compressed very light spring between them. They are not attached to the spring. After they are released and have both moved free of the spring the heavier block will have more kinetic energy than the lighter block. the magnitude of the momentum of the heavier block will be greater than the magnitude of the momentum of the lighter block. the lighter block will have more kinetic energy than the heavier block. both blocks will have equal speeds. both blocks will both have the same amount of kinetic energy.

incorrect

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? 6.2 m/s2 5.5 m/s2 4.7 m/s2 5.2 m/s2

incorrect

A pilot drops a package from a plane flying horizontally at a constant speed. Neglecting air resistance, when the package hits the ground the horizontal location of the plane will depend of the speed of the plane when the package was released. be behind the package. be over the package. be in front of the package.

incorrect

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 neither the cargo nor the plane change speed. both the cargo and the plane speed up. the plane speeds up and the cargo slows down. the cargo slows down but the plane does not change speed. the plane speeds up but the cargo does not change speed.

incorrect

A test rocket is fired straight up from rest with a net acceleration of 20.0 m/s2. After 4.00 seconds the motor turns off, but the rocket continues to coast upward with no appreciable air resistance. What maximum elevation does the rocket reach? 487 m 408 m 320 m 160 m 327 m

incorrect

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? 85 N 61 N 92 N 75 N

incorrect

Alice and Tom dive from an overhang into the lake below. Tom simply drops straight down from the edge, but Alice takes a running start and jumps with an initial horizontal velocity of 25 m/s. Neither person experiences any significant air resistance. Compare the time it takes each of them to reach the lake below. Tom reaches the surface of the lake first. Alice reaches the surface of the lake first. Alice and Tom will reach the surface of the lake at the same time.

incorrect

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. The speed of the object is decreasing. increasing. constant in time.

incorrect

For general projectile motion, when the projectile is at the highest point of its trajectory the horizontal and vertical components of its velocity are zero. its velocity is perpendicular to the acceleration. its acceleration is zero. its velocity and acceleration are both zero. the horizontal component of its velocity is zero.

incorrect

Projectile Motion: For general projectile motion with no air resistance, the horizontal component of a projectile's velocity remains a non-zero constant. continuously increases. continuously decreases. first decreases and then increases. remains zero.

incorrect

Suppose you are playing hockey on a new-age ice surface for which there is no friction between the ice and the hockey puck. You wind up and hit the puck as hard as you can. After the puck loses contact with your stick, the puck will speed up a little, and then slow down. speed up a little, and then move at a constant speed. start to slow down. not slow down or speed up.

incorrect

Two objects, one of mass m and the other of mass 2m, are dropped from the top of a building. When they hit the ground both of them will have the same kinetic energy. the heavier one will have four times the kinetic energy of the lighter one. the heavier one will have twice the kinetic energy of the lighter one. the heavier one will have 2√2 times the kinetic energy of the lighter one.

incorrect

has picture A 15-g bullet is shot vertically into an 2-kg block. The block lifts upward 8.0 mm (see the figure). The bullet penetrates the block and comes to rest in it in a time interval of 0.0010 s. Assume the force on the bullet is constant during penetration and that air resistance is negligible. The initial kinetic energy of the bullet is closest to 0.0012 J.0.16 J.10 J.21 J.14 J.

incorrect

Satellite Motion: A satellite orbits the Earth once every 6.0 hours in a circle. G = 6.67 × 10-11 N ∙ m2/kg2, M earth = 5.97 × 1024 kg. What is the magnitude of the acceleration of the satellite? Express your answer with the appropriate units. What is the direction of the acceleration of the satellite? toward the center of the earth away from the center of the earth in the forward direction in the backward direction

incorrect, toward the center of the earth

Uniform Circular Motion: When an object moves in uniform circular motion, the direction of its acceleration is is directed away from the center of its circular path. depends on the speed of the object. is directed toward the center of its circular path. in the opposite direction of its velocity vector. in the same direction as its velocity vector.

is directed toward the center of its circular path.

(has picture) Two bodies P and Q on a smooth horizontal surface are connected by a light cord. The mass of P is greater than that of Q. A horizontal force F ⃗ F → (of magnitude F) is applied to Q as shown in the figure, accelerating the bodies to the right. The magnitude of the force exerted by the connecting cord on body P will be less than F but not zero. equal to F. greater than F. zero.

less than F but not zero.

(has picture) A brick is resting on a rough incline as shown in the figure. The friction force acting on the brick, along the incline, is greater than the weight of the brick. zero. less than the weight of the brick. equal to the weight of the brick.

less than the weight of the brick.

(has picture)General Questions: A girl attaches a rock to a string, which she then swings counter-clockwise in a horizontal circle. The string breaks at point P in the figure, which shows a bird's-eye view (as seen from above). Which path (A-E) will the rock follow? Path A Path B Path C Path D Path E

path b

Uniform Circular Motion: A car goes around a circular curve on a horizontal road at constant speed. What is the direction of the friction force on the car due to the road? perpendicular to the curve outward tangent to the curve in the forward direction perpendicular to the curve inward tangent to the curve opposite to the direction of the car's motion There is no friction on the car because its speed is constant.

perpendicular to the curve inward

(has picture) 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 with a box of mass 2m both boxes will reach the same maximum height on the incline. both boxes will have the same speed just as they move free of the spring. just as it moves free of the spring, the lighter box will be moving twice as fast as the heavier box. the lighter box will go twice as high up the incline as the heavier box. just as it moves free of the spring, the heavier box will have twice as much kinetic energy as the lighter box.

the lighter box will go twice as high up the incline as the heavier box.

n an INELASTIC collision between two objects both the momentum and the kinetic energy of the system are conserved. the kinetic energy of the system is conserved, but the momentum of the system is not conserved. the momentum of the system is conserved but the kinetic energy of the system is not conserved. the kinetic energy of each object is conserved. the momentum of each object is conserved.

the momentum of the system is conserved but the kinetic energy of the system is not conserved.

Rotational Kinetic Energy: Suppose a solid uniform sphere of mass M and radius R rolls without slipping down an inclined plane starting from rest. The angular velocity of the sphere at the bottom of the incline depends on the radius of the sphere. the mass of the sphere. both the mass and the radius of the sphere. neither the mass nor the radius of the sphere.

the radius of the sphere.

Alice and Tom dive from an overhang into the lake below. Tom simply drops straight down from the edge, but Alice takes a running start and jumps with an initial horizontal velocity of 25 m/s. Neither person experiences any significant air resistance. Just as they reach the lake below the speed of Alice is larger than that of Tom. the splashdown speed of Alice is larger than that of Tom. the speed of Alice will always be 25 m/s larger than that of Tom. the speed of Tom will always be 9.8 m/s larger than that of Alice. they will both have the same speed.

the speed of Alice is larger than that of Tom.