AP physics
d) 25cos40
A ball is launch at 25 m/s at a 40 degree angle. What is the velocity of the ball at the peak of its path? a) 25 m/s b) 0 m/s c) 25sin40 d) 25cos40 e) 9.8 m/s
d)
A projectile is fired with initial velocity vo at an angle with the horizontal and follows the trajectory shown above. Which of the following pairs of graphs best represents the vertical components of the velocity and acceleration, v and a, respectively, of the projectile as functions of time t?
0 m/s2
A student pushes on a 160N box with a force of 50N at a angle of 35. The coefficient of static friction between the box and the surface is 0.40 and the coefficient of kinetic friction between is 0.20. The magnitude of the acceleration of the box is most nearly a) 0 m/s2 b) 0.2 m/s2 c) 0.9 m/s2 d) none of these answers are reasonably close
a) I only
A whiffle ball is tossed straight up, reaches a highest point, and falls back down. Air resistance is negligible. Which of the following statements are true? I. The balls speed is zero at the highest point II. The balls acceleration is zero at the highest point. III. The ball takes a longer time to travel up to the highest point than to fall back down. a) I only b) II only c) I & II only d) I & III only
c) D > A > C > B
Which of the following best ranks the average speed of the car in each region? a) A > B > C > D b) A > C > B > D c) D > A > C > B d) A > C > D > B e) D > C > B > A
b) the new normal force is less than FN
A crate is on a horizontal frictionless surface. A force of magnitude F is exerted on the crate at an angle to the horizontal, causing the crate to slide to the right. The surface a normal force of FN on the crate. While F is kept constant the angle is not doubled but still less than 90. Assume the crate remains in contact with the surface. How does the new normal force exerted on the crate compare to FN? a) the new normal force is greater than FN b) the new normal force is less than FN c) the new normal force is equal to FN d) the new normal force is greater or less than FN depending on the value of 🚫 (angle)
c) 2d
A diver initially moving horizontally with speed v dives off the edge of a vertical cliff and lands in the water a distance d from the base of the cliff. How far from the base of the cliff would the diver have landed if the diver initially had been moving horizontally with speed 2v? a) d b) 1/2d c) 2d d) 4d e) it cannot be determined unless the height of the cliff is known
a) P > f and N > W
A homeowner pushed a lawn mower across a horizontal latch of grass with a constant speed by applying a force P. The arrow in the diagram correctly indicate the directions but not necessarily the magnitudes of the various forces on the lawn mower. Which of the following relations among the various force magnitudes, W, f, N, P is correct? a) P > f and N > W b) P < f and N = W c) P > f and N < W d) P = f and N > W
b) 10.0 m/s
A manufacturer of model rocket engines provides a force time graph for one of its engines. Neglecting any change in mass of the engines fuel and air resistance, what maximum velocity could a 2000g rocket car reach from rest on a frictionless horizontal track if equipped with this engine? a) 7.50 m/s b) 10.0 m/s c) 20.0 m/s d) 75.0 m/s
a)
A rocket is continuously firing its engines as it accelerates away from the Earth. For the first kilometer of its ascent, the mass of fuel ejected is small compared to the mass of the rocket. For this distance, which of the following indicates the changes, if any, in the kinetic energy of the rocket, the gravitational potential energy of the Earth-rocket system and the mechanical energy of the Earth- rocket system?
a) I and II
A soccer ball is rolling a field with a speed +Vinitial when a student runs up and kicks the ball in the same direction that is was traveling so that is now has a greater speed in the same direction +Vfinal. Your physics teacher wants you to take measurements that will allow you to calculate the rough estimate of the impulse applied to the ball by the students foot. Which measurements would you want to make so that you could calculate this impulse? I) the distance and times the ball traveled both before and after the kick II) the mass of the ball III) the force applied to the ball IV) the time that the foot and ball were in contact a) I and II b) I and III c) I and IV d) II and III e) II and IV
b)
A spring is attached to a block that is on a inclined plane. Which of the following free body diagrams is correct?
a) F < mg
An elevator carrying a person of mass m has a upwards velocity but is slowing down. How does the magnitude F of the force exerted on the person by the elevator floor compare with the magnitude mg of the gravitational force? a) F < mg b) F = mg c) F > mg d) F can be greater than it less than mg, depending on the speed of the elevator
d) 4h
An object is released from rest and falls a distance h during the first second of time. How far will it fall during in 2 seconds? a) h b) 2h c) 3h d) 4h
c) I and III only
As an object falls freely, it's magnitude of: I. Velocity increases II. Acceleration increases. III. Displacement increases a) I only b) I and II only c) I and III only d) II and III
c)
Assume the elevator is moving at constant speed, and consider the bottom box on the stack that has two boxes of mass 2m. Let Ffloor be the force exerted by the floor, Fg be the force exerted by gravity on the box, and Fbox be the force exerted by the top box on the bottom box. Which of the following best represents the forces exerted on the bottom box
d) the magnitude of the force exerted by each object in the tractor is equal, because the tractor exerts an equal force on each object
Each of the figures shows a tractor attached to an object. The tractor exerts the same constant force F on each object in every case. Which of the following is a true statement about an object and the relative magnitude of the force exerted by the object in the tractor? a) the magnitude of the force exerted by the truck on the tractor is greatest, because the resulting motion is in the direction opposite the tractors pull b) the magnitude of the force exerted by the boulder on the tractor is least, because no motion results c) the magnitude of the force exerted by the wagon on the tractor is least, because the resulting motion is in the direction of the tractors pull d) the magnitude of the force exerted by each object in the tractor is equal, because the tractor exerts an equal force on each object
a) AB
For which segment does the cart move the greatest distance? a) AB b) BC c) CD d) DE
d) C = E > A > B
Rank the average magnitude of accelerations of the car in regions A, B, C and E. a) A < B > C = E b) B = A > C = E c) B > A = C = E d) C = E > A > B e) A > B > C > E
c) B > A = C = E
Rank the average speed of the car in regions A, B, C, and E a) A < B > C = E b) B = A > C = E c) B > A = C = E d) B > A = C > E e) A > B > C > E
a) D>A>C>B
Rank the four block shown for their change in momentum from largest change to smallest change. Each block is in motion for 10.0 seconds. a) D>A>C>B b) A>D>C>B c) A>B>D>C d) D>A>B>C
c) push of box G against Susan
Susan pushes a box G that is next to box H, causing both boxes to slide along the floor as shown. The reaction force of Susan's push is the: a) upward force of the floor on box G b) push of box H on box G c) push of box G against Susan d) push of box G on box H
d) force gravity and force normal
The box in the diagram is sliding to the right across a horizontal surface, under the influence of the forces shown. Which force (or forces) does zero work on the box? a) force gravity b) force gravity and force friction c) force friction d) force gravity and force Normal
c)
The figure shows a truck pulling three crates across a rough road. Which of the following shows the direction of all the horizontal forces acting in crate 2?
d)
The velocity of a projectile at launch has a horizontal component Vh and a vertical component Vv. Air resistance is negligible. When the projectile is at the highest point of its trajectory, which of the following shows the vertical and horizontal components of its velocity and the vertical component of its acceleration?
d) the object must have been thrown straight up into the air and then comes back down
The vertical velocity vs time motion for an object is shown above, with positive velocity indicating a speed in the upward direction. Based on the graph, a) the object must be traveling in a negative direction throughout its motion b) the object must be traveling with a constant velocity throughout its motion c) the object magnitude of acceleration is changing d) the object must have been thrown straight up into the air and then comes back down
d) motion of an object with no net force acting on it
This position-time graph is typical of which type of motion a) motion of an object with an increasing net force acting upon it b) motion with zero velocity c) motion with a constant positive net force acting on it d) motion of an object with no net force acting on it e) motion of an object with a negative net force acting on it
c) motion with a constant positive net force acting on it
This velocity-time graph is typical of which type of motion a) motion of an object with an increasing net force acting upon it b) motion with zero velocity c) motion with a constant positive net force acting on it d) motion of an object with a negative net force acting on it e) motion of an object with no net force acting on it
c)
Three identical projectiles are launched from the same elevation at different angles. Projectile 1 has a speed of V1, projectile 2 has a speed of V2 and projectile 3 has a speed of V3. If you know that V1 < V2 < V3 and that all of the projectiles reach the same maximum height, which is the appropriate relation for their launch angle?
b) 2.00m/s; 2.00m/s; elastic
Two blocks slide on a horizontal friction less surface and collide as diagrammed. The velocities and kinetic energy for the 1.00kg block are best answered by which of the following choices?
c) C
Which block has the greatest speed just before hitting the ground? a) A b) B c) C d) the blocks reach the ground with the same speed
b) B
Which block takes the longest to reach the ground? a) A b) B c) C d) the blocks take the same time to reach the ground
b) the car is moving a constant speed in the negative direction
Which of the following best describes the motion of the car in region a D of the graph? a) the car slows down b) the car is moving a constant speed in the negative direction c) the car is moving down an incline d) the car is speeding up in the negative direction e) the car moves from a position of 20 to a position of 25
d) the vertical speed decreases on the way up and increases on the way down
Which one of the following statements is true concerning the motion of an ideal projectile launched at an angle of 45 degrees to the horizontal? a) the acceleration vector points opposite to the velocity vector on the way up and in the same direction as the velocity vector on the way down b) the speed at the top of the trajectory is zero c) the objects total speed remains constant during the entire flight d) the vertical speed decreases on the way up and increases on the way down
b) W-Fsin
A block of weight W is pulled along a horizontal surface at constant speed v by a force F, which acts at an angle of 🚫 with the horizontal, as shown. The normal force exerted on the block by the surface has magnitude a) W-Fcos b) W- Fsin c) W d) W+Fsin e) W+Fcos
b) Fcos = FN c) Fsin = Fg +/- Ff
A block is held at rest against a wall by a force of magnitude F exerted at an angle from the horizontal. Let Fg be the gravitational force exerted by the Earth on the block, FN be the normal force exerted by the wall on the block, and Ff be the frictional force exerted by the wall on the block. Which of the following statements about the magnitudes of the forces on the block must be true? SELECT TWO a) F = Fg/Sin b) Fcos = FN c) Fsin = Fg +/- Ff d) F = Fg + FN +/- Ff
c) 3rd law of motion
A body cannot exert a force on itself. This statement is a direct consequence on which of Newton's Laws? a) 1st law of motion b) 2nd law of motion c) 3rd law of motion d) none because an object CAN exert a force in itself
c) the force of friction exerted by the ground on the person
A person is running on a track. Which of the following forces propels the runner forward? a) the normal force exerted by the ground on the person b) the normal force exerted by the person on the ground c) the force of friction exerted by the ground on the person d) the force of friction exerted by the person on the ground
b) the inertia of the coin keeps moving tangent to the circle
A physics student rides a roller coaster and places a quarter on their knee before they go around a loop. The student notices that the quarter remains on their knee. What explains this physics phenomena? a) the force of gravity pushed the quarter into the students knee b) the inertia of the coin keeps moving tangent to the circle c) the coin needed a normal force from the students knee to keep it moving in a circle d) there is a force that acts on objects called inertia that is the natural tendency of an object to want to continue doing what it is already doing
a) 2/3
A train engine can exert a maximum pulling force of Fmax. By what factor would the resulting maximum acceleration differ if the mass of an entire single engine train were tripled AND the number of pulling engines, each pulling Fmax doubled? Assume friction is negligible. a) 2/3 b) 1/3 c) 3/2 d) 2
c) is not affected by the collision because there were no external forces acting on the gliders
An inelastic Collision occurred between two identical gliders in an air track. The first glider moving with a velocity of 1.00m/s struck a second glider that was at rest. After the collision, both gliders moved as a unit with a velocity of 5.0m/s. Analysis shows the velocity of the center of mass a) increases after the collision because both masses are moving b) decreases after the collision because both masses are moving c) is not affected by the collision because there were no external forces acting on the gliders d) will increase only if both gliders were moving initially in the same direction because the final velocity would be larger
c) FN= mgcos d) FT= Fs + FgSin
Referring to the previous question, Which of the following equations are correct if the block is in static equilibrium? PICK TWO a) FN= FgSin b) Fs = FT c) FN= mgcos d) FT= Fs + FgSin
d) 25J
The graph shows the force acting on a car over some distance. Assume the car starts at rest and there are no frictional forces acting on the car. How much work was done on the car between 0m and 5m? a) 0J b) 50J c) 0.5J d) 25J
c)
Two identical carts are free to move along a straight track. At time T1, cart X is moving at 2.0 m/s when it collided with and sticks to cart Y, which is initially at rest. Which of the following graphs best shows the velocity of cart X before and after the collision?
a) car Y is behind car X
Which of the following is true at time t= 20 sec? a) Car Y is behind car X b) car Y is passing car X c) Car Y is infront of car X d) car X is accelerating faster than car Y
a & d
Which of the following pairs of graphs shows the distance traveled versus time and the speed versus time for an object uniformly accelerated from rest? PICK TWO
d) a= g(sin - ucos)
A box of unknown mass (m) slides down a plane inclined at angle. The plane has a coefficient of friction (u). Which of the following expressions would you use to calculate the rate of acceleration? a) a= g(sin - ugcos)/m b) a= g(cos - ugsin)/m c) a= m(sin - ugcos)/g d) a= g(sin - ucos) e) a= g(cos - usin)
c) less than the blocks gravitational potential energy when it was released because the gravitational potential energy was converted both to thermal and to kinetic energy
A 1-kg object is released from rest from the top a roughed surface incline. The object slides without rotating to the bottom of the incline. The object's kinetic energy at the bottom must be a) equal to the blocks gravitational potential energy when it was released, because the total mechanical energy must be conserved b) equal to the blocks gravitational potential energy when it was released because the gain in kinetic energy compensated for the mechanical energy lost to thermal energy on the rough incline c) less than the blocks gravitational potential energy when it was released because the gravitational potential energy was converted both to thermal and to kinetic energy d) less than the blocks gravitational potential energy when it was released because the work done by the friction force must be greater than the blocks gain in kinetic energy
b) 8.03 m/s
A ball is launched at 25 m/s at a 40 degree angle. What is the average vertical velocity of the ball from time t=0 until the time the ball reaches the peak of its path? a) 0 m/s b) 8.03 m/s c) 16.07 m/s d) 12.5 m/s e) 9.58 m/s
d) the normal force exerted on the broom by the wall
A broom at rest is leaning against a walls at an angle. Which of the following forces must have the same magnitude as the frictional force exerted on the broom by the floor? a) the force of gravity on the broom b) the normal force exerted on the broom by the floor c) the frictional force exerted on the broom by the wall d) the normal force exerted on the broom by the wall
d) the bullet fired out of the gun has a greater acceleration
A bullet is fired from a gun with a horizontal launch angle. At the same time a second bullet is dropped from the same height. Which of the following statements is FALSE? a) the bullet fired from the gun has a greater velocity when it hits the ground b) both bullets hit the ground at the same time c) the bullets both have the same vertical displacement d) the bullet fired out of the gun has a greater acceleration
b)
A bus initially traveling north at a constant speed. As the bus starts to make a turn to the left without changing speed, a passenger notices a box on the floor starts sliding toward the right side of the bus. Which of the following top views of the box, when correctly labeled, would best represent all the horizontal forces exerted on the box as it starts sliding?
c) 🔺KA <🔺KB ; 🔺UA = 🔺UB
A child slides from rest down slides A and B. The slides are the same height and the coefficient of friction between the slides and the child is the same for both slides. Which of the following compares the changes in 🔺K in the kinetic energy of the child and the 🔺U in the potential energy of the child-Earth system for the two slides? a) 🔺KA = 🔺KB ; 🔺UA = 🔺UB b) 🔺KA <🔺KB ; 🔺UA >🔺UB c) 🔺KA <🔺KB ; 🔺UA = 🔺UB d) 🔺KA >🔺KB ; 🔺UA >🔺UB
d) 2.7 J/s
A force is applied to an object over a certain displacement as shown in figure A. How much power was exerted in moving the object .090m, if this displacement occurred over a .05 time interval? a) 5.4 J/s b) 0.27 J/s c) 0.54 J/s d) 2.7 J/s
b) both the drop height and the fall time of the sphere
A group of students is designing an experiment to verify the free fall acceleration rate in Earth. They plan to evacuate air from a bell jar using a vacuum pump and then use a remotely controlled apparatus within the vacuum to drop a spherical metal object from rest. The group does not have means to measure the acceleration directly, so they instead plan to measure other quantities about the sphere and its motion and then will calculate an experimental value for acceleration. Which of the following measurements would provide the group with enough information to determine the spheres acceleration rate without making any additional measurements? a) only the drop height of the sphere b) both the drop height and the fall time of the sphere c) the drop height, fall time and mass of sphere d) the drop height, fall time and landing speed of the sphere
b)
From the top of a high cliff, a ball is thrown horizontally with initial speed Vo. Which of the following graphs best represents the balls kinetic energy K as a function of time t?
a) the two magnitudes are always equal in each of the stacks
Refer to figure A. The stack of boxes shown in the figure above are inside an elevator that is moving upward. The masses of the boxes are given in terms of the mass M of the lightest box. How does the magnitude of the force exerted by the top box on the bottom box compare with the magnitude of the force exerted by the bottom box on the top box? a) the two magnitudes are always equal in each of the stacks b) the two magnitudes are always different in each of the two stacks c) the two magnitudes are equal when the boxes have equal masses and different when the boxes have different masses d) the two magnitudes are equal when the elevator is moving at constant speed and different when it is accelerating
b) no forces were responsible for Steve's movement
Steve is standing facing forward in a moving bus. What force causes Steve to move suddenly forward when the bus comes to an abrupt stop? a) force due to air pressure inside the previously moving bus b) no forces were responsible for Steve's movement c) force due to kinetic friction between Steve and the floor of the bus d) force due to stored kinetic energy
b) arrow B arrives first
Two arrows are launched at the same time with the same speed. Arrow A at an angle greater than 45 degrees, and arrow B at an angle less than 45 degrees. Both land at the same spot on the ground. Which arrow arrives first? a) arrow A arrives first b) arrow B arrives first c) they both arrive together d) it depends on the elevation where the arrows land
d) inelastic because only momentum is conserved
Two bodies move on a frictionless surface as shown. The collision is a) elastic since both kinetic energy and momentum are conserved b) elastic since only momentum are conserved c) inelastic since both kinetic energy and momentum are conserved d) inelastic because only momentum is conserved
d) 10 m/s^2
What is the magnitude of the average acceleration of the car in region A? a) 0 m/s^2 b) 3 m/s^2 c) 15 m/s^2 d) 10 m/s^2 e) 30 m/s^2
e) 5 m/s, -25 m/s
What is the velocity of the car in region C and D, respectively? a) +25 m/s, -125 m/s b) 5 m/s, 25 m/s c) 25 m/s, 125 m/s d) 5 m/s, 5 m/s e) 5 m/s, -25 m/s
c) D > A > C > B
Which of the following best ranks the magnitude of the displacement of the car in each region? a) A > B > C > D b) A > C > B > D c) D > A > C > B d) A > C > D > B e) D > C > B > A
c) is in the opposite direction of the motion e) is specific to a combination of materials
Which of the following statements are true regarding the coefficient of kinetic friction: select TWO a) is in the opposite direction of the force b) can have units in Newton c) is in the opposite direction of the motion d) is greater than the coefficient of static friction e) is specific to a combination of materials
a) it is slowing down until it reverses direction and speeds back up again
Which of the following best describes the motion of the car in regions C, D, and E of the following velocity vs time graph? a) it is slowing down until it reversed direction and speeds back up again b) it moves at a constant velocity in a negative direction c) it accelerates at a constant, nonzero acceleration except at point C when it's acceleration is zero d) it's position changes at a constant rate e) it moves at a constant, positive acceleration throughout the trip
b)
Which of the following correcting depicts the directions for line segments A, C, E and F? (Refer back to velocity vs time graph)
d) Acd > Aab > Ade > Abc
Which of the following correctly ranks the magnitude of the average acceleration of the cart during the four sections of the graph? a) Acd > Aab > Abc > Ade b) Abc > Aab > Acd > Ade c) Aab > Abc > Ade > Acd d) Acd > Aab > Ade > Abc
a)
Which of the following depicts the correct distance and displacement of the object after 9 seconds? (Refer back to velocity vs time graph)
c) car 2 and car 1 have the same average velocity
Which of the following is true at time t=40 seconds? a) car 3 is behind car 2 b) car 1 is infront of car 3 c) car 2 and car 1 have the same average velocity d) car 3 is accelerating faster than car 2
c)
Which of the following sets of graphs show a correct relationship between the graphs of Positions, Velocity, and Acceleration vs. Time graphs?
a) increase since a variable but positive force acts on the objects as shown by the area under the force-time graph
An object moving in the positive x direction experiences a variable force shown in the force vs time graph. The momentum of the system will a) increase since a variable but positive force acts on the objects as shown by the area under the force-time graph b) decrease since the force applied to the object drops to zero as shown in the graph c) increases from 1.00 to 3.00 seconds and then decrease from 3.00 to 4.00 seconds as shown in the force vs time graph d) be undetermined since the mass of the object is not included in the problem
c) KEb > KEc > KEd = KEa
A ball is dropped from a height h1, at position A and rebounds to a lower height h2, at Position D as shown in the diagram. Position B represents the location of the ball just before it lands and position C is the location of the ball just after it leaves the ground. Assume the effect of air resistance on the ball is negligible. Which of the following choices indicates the correct ranking (greatest to least) of the kinetic energy (KE) of the ball at each of the positions in the diagram? a) KEa > KEd > KEb = KEc b) KEa = KEd > KEb > KEc c) KEb > KEc > KEd = KEa d) KEc > KEb > KEa = KEd
b) the center of mass of all pieces continues on the same trajectory as the baseball before the explosion
A baseball is thrown through the air with an initial angle of 45. Midway through the flight the baseball suddenly explodes into many pieces. Which of the following is true assuming no outside forces are present? a) All pieces fall to the ground under the influence of gravity. All pieces have zero horizontal velocity after the explosion b) the center of mass of all the pieces continues on the same trajectory as the baseball before the explosion c) all individual pieces continue on the same trajectory as the baseball before the explosion d) the center of mass of all pieces has a greater net velocity after the explosion compared to before the explosion
c) only the mass of block A and the distance block A falls to reach the floor
A block hangs from a light string that passes over a light pulley and is attached to block B, which is on a level horizontal frictionless table. Students are to determine the mass of the block B from the motion of the two block system after it is released from rest. They plan to measure the time it takes for block A to reach the floor. The students must also take which of the following measurements to determine the mass of block B? a) only the mass of block A b) only the distance block A falls to reach the floor c) only the mass of block A and the distance block A falls to reach the floor d) the mass of block A, the distance block A falls to reach the floor, and the mass of the pulley
a)
A lion is running a constant speed towards a gazelle that is standing still. After several seconds the gazelle notices the lion and accelerated directly towards him, hoping to pass the lion and force him to reverse direction. As the gazelle accelerated towards and past the lion, the lion changes direction and accelerated in pursuit of the gazelle. The lion and gazelle eventually each reach constant but different speeds. Which of the following sets of graphs shows a reasonable representation of the velocities of the lion and gazelle as function of time?
d) the acceleration of the plastic balls is not uniform
A student is testing the kinematic equations for uniformly accelerated motion by measuring the time it takes for the light-weight plastic balls to fall to the floor from a height of 3m in the lab. The student predicts the time to fall using g as 9.80 m/s2 but finds the measured time to be 35% greater. Which of the following REALISTICALLY is the most likely cause of the large percent error? a) the acceleration due to gravity is 70% greater than 9.80 m/s2 at this location b) the acceleration due to gravity is 70% less than 9.80 m/s2 at this location c) air resistance increases the downward acceleration d) the acceleration of the plastic balls is not uniform
c) the velocity of the center of mass remains at zero because the skaters were initially at rest and due to recoil, they move in opposite directions with speeds proportional to their mass
A student observes two skaters, m1= 50.0 kg and m2= 60.0 kg, initially at rest in a frictionless ice pushing off one another. When the skaters recoil from each other, the student correctly predicts that a) the velocity of the smaller skater is larger because the larger skater exerts a large force on the smaller skater b) the velocity of the smaller skater is equal to the velocity of the larger skater because action-reaction forces were exerted on both c) the velocity of the center of mass remains at zero because the skaters were initially at rest and due to recoil, they move in opposite directions with speeds proportional to their mass d) the velocity of the skaters decreases because gravitational forces on the skaters have not changed in the interaction and there is no transfer of gravitational energy to kinetic energy
d) block 2, because the final velocity is closer to the initial velocity of block 2 than it is to the initial velocity of block 1
Block 1 of mass1 and Block 2 of mass2 are sliding along the same line on a horizontal frictionless surface when they collide at tc. The graph shows the velocities of the blocks as a function of time. Which block has the greater mass, and what information indicates this? a) Block 1, because it had a greater speed before the collision b) block 1, because the velocity after the collision is in the same direction as it's velocity before the collision c) block 2, because it had a smaller speed before the collision d) block 2, because the final velocity is closer to the initial velocity of block 2 than it is to the initial velocity of block 1
b) (FB = FA) < Fg
Box A of mass m sits on the floor of an elevator, with box B of mass 2m on top of it, as shown in the figure. The elevator is moving upward and slowing down. FA is the magnitude of the force exerted on box A by box B, FB is the magnitude of the force exerted on box B by box A, and Fg is the magnitude of the gravitational force exerted on box B. Which of the following ranks the forces in order of increasing magnitude? a) FB = FA = Fg b) (FB = FA) < Fg c) FB < (FA = Fg) d) Fg < FB < FA
a) measure height of the cliff. Use work-energy theorem to find the change in kinetic energy of the rock and the final velocity of the rock before it strikes the bottom of the cliff
Consider a rock dropped from rest from the top of a tall cliff. Which of the following procedures described below is the best method to determine the final velocity of the rock just before it strikes the ground? a) measure the height of the cliff. Use the work-energy theorem to find the change in kinetic energy of the rock and the final velocity of the rock before it strikes the bottom of the cliff b) measure the diameter of the rock. Use the work-energy theorem to find the change in kinetic energy of the rock and the final velocity of the rock before it strikes the bottom of the cliff c) measure the mass of the rock. Use the work-energy theorem to find the change in kinetic energy of the rock and the final velocity of the rock before it strikes the bottom of the cliff d) measure the mass of the rock and the initial velocity of the rock. Use the work-energy theorem to find the change in kinetic energy of the rock and the final velocity of the rock before it strikes the bottom of the cliff
b) the kinetic energy of puck m1 is greater than the kinetic energy of puck m2
Consider the diagram depicting two pucks, where m1 is half the mass of mass m2. Both pucks start from rest and are given a push with a force (F) for a given time (t). At the end of time this does the kinetic energy of puck m1 compare to the kinetic energy of puck m2? a) the kinetic energy of m1 is less than the kinetic energy of puck m2 b) the kinetic energy of puck m1 is greater than the kinetic energy of puck m2 c) the kinetic energy of puck m1 is equal to the kinetic energy of puck m2
d) 2 m/s2 to the left
The figure shows the forces exerted on a block that is sliding on a horizontal surface: the gravitational force of 40 N, the 40 N normal force exerted by the surface, and a frictional force exerted to the left. The coefficient of friction between the block and the surface is 0.20. The acceleration of the block is most nearly, a) 1 m/s2 to the right b) 1 m/s2 to the left c) 2 m/s2 to the right d) 2 m/s2 to the left
a)
The free fall trajectory of an object thrown horizontally from the top of a building is shown as the dashed line in the figure. Which sets of arrows best correspond to the directions of the velocity and of the acceleration for the object at the point labeled P on the trajectory?
c) acceleration due to gravity
The graph (weight in Newtons vs mass of stopper in kilograms) shows the relationship between the mass of a number of rubber stoppers and their resulting weight on some far-off planet. The slope of the graph is a representation of the: a) mass of stopper b) density of a stopper c) acceleration due to gravity d) number of stoppers for each unit of weight
a)
The graph to the right shows velocity v versus time t for an object in linear motion. Which of the following is a possible graph of position x versus time t for this object?
