AP Physics 1 - Semester 2 Final

A 200-N sled of slides down a frictionless hillside that rises at 37° above the horizontal. What is the magnitude of the force that the surface of the hill exerts on the sled? 0 N 120 N 150 N 160 N 200 N

160 N

If a vector A has components Ax>0, and Ay<0, then the angle that this vector makes with the positive x-axis must be in the range 180∘ to 270∘ 270∘ to 360∘ 90∘ to 180∘ 0∘ to 90∘ It cannot be determined without additional information.

270∘ to 360∘

A person is using a rope to lower a 5.0-N bucket into a well with a constant speed of 2.0 m/s. What is the magnitude of the force exerted by the rope on the bucket? 10 N 5.0 N 49 N 0.00 N 2.0 N

5.0 N

Which of the following quantities has units of a velocity? (There could be more than one correct choice.) -120 m/s 9.8 m/s2 downward 9.8 m/s downward 186,000 mi 40 km southwest

9.8 m/s downward

If a vector A has components Ax<0, and Ay>0, then the angle that this vector makes with the positive x-axis must be in the range 270∘ to 360∘ 0∘ to 90∘ 90∘ to 180∘ 180∘ to 270∘ It cannot be determined without additional information.

90∘ to 180∘

Which of the following situations is impossible? An object has constant non-zero acceleration and changing velocity. An object has zero velocity but non-zero acceleration. An object has constant non-zero velocity and changing acceleration. An object has velocity directed east and acceleration directed east. An object has velocity directed east and acceleration directed west.

An object has constant non-zero velocity and changing acceleration.

Mary and Debra stand on a snow-covered roof. They both throw snowballs with the same initial speed, but in different directions. Mary throws her snowball downward, at 30° below the horizontal; Debra throws her snowball upward, at 30° above the horizontal. Which of the following statements are true about just as the snowballs reach the ground below? (There could be more than one correct choice.) Mary's snowball will have a higher speed than Debra's snowball. Both snowballs hit the ground at the same time. Both snowballs will hit the ground with the same speed. Mary's snowball reaches the ground before Debra's snowball. Debra's snowball will have a higher speed than Mary's snowball.

Both snowballs will hit the ground with the same speed. Mary's snowball reaches the ground before Debra's snowball.

A 20-ton truck collides with a 1500-lb car. Which of the following statements must be true? During the collision, the force on the truck is greater than the force on the car. The car did not slow down during the collision, but the truck did. During the collision, the force on the truck is equal to the force on the car. The truck did not slow down during the collision, but the car did. During the collision, the force on the truck is smaller than the force on the car.

During the collision, the force on the truck is equal to the force on the car.

A ball is thrown downward in the absence of air resistance. After it has been released, which statement(s) concerning its acceleration is correct? (There could be more than one correct choice.) Its acceleration is constant. Its acceleration is zero. Its acceleration is constantly increasing. Its acceleration is constantly decreasing. Its acceleration is greater than g.

Its acceleration is constant.

Suppose that a car traveling to the east (+x direction) begins to slow down as it approaches a traffic light. Which statement concerning its acceleration must be correct? Its acceleration is in the -x direction. Its acceleration is decreasing in magnitude as the car slows down. Its acceleration is in the +x direction. Its acceleration is zero.

Its acceleration is in the -x direction.

A rock is thrown from the upper edge of a tall cliff at some angle above the horizontal. It reaches its highest point and starts falling down. Which of the following statements about the rock's motion are true just before it hits the ground? (There could be more than one correct choice.) Its vertical velocity component is the same as it was just as it was launched. Its velocity is vertical. Its horizontal velocity component is zero. Its horizontal velocity component is the same as it was just as it was launched. Its speed is the same as it was just as it was launched.

Its horizontal velocity component is the same as it was just as it was launched.

The acceleration due to gravity is lower on the Moon than on Earth. Which one of the following statements is true about the mass and weight of an astronaut on the Moon's surface, compared to Earth? Mass is the same, weight is less. Both mass and weight are less. Mass is less, weight is the same. Both mass and weight are the same.

Mass is the same, weight is less.

Which of the following quantities are units of momentum? (There could be more than one correct choice.) Check all that apply. N • s kg ∙ m2/s2 kg • m/s N • m Fowlers

N • s kg • m/s Fowlers

A crate is sliding down an inclined ramp at a constant speed of 0.55 m/s. The vector sum of all the forces acting on this crate must point down the ramp. vertically downward. perpendicular to the ramp. up the ramp. None of the above choices is correct.

None of the above choices is correct.

As shown in the figure, a woman is straining to lift a large crate, but without success because it is too heavy. We denote the forces on the crate as follows: P is the magnitude of the upward force being exerted on the crate by the person, C is the magnitude of the vertical contact force on the crate by the floor, and W is the weight of the crate. How are the magnitudes of these forces related while the person is trying unsuccessfully to lift the crate? The figure shows a crate on the horizontal plane. The crate has two handles on its top side. The woman standing on the plane tries to lift the handles. P + C > W P + C < W P = C P + C = W

P + C = W

A push of magnitude P acts on a box of weight W as shown in the figure. The push is directed at an angle θ below the horizontal, and the box remains a rest. The box rests on a horizontal surface that has some friction with the box. The friction force on the box due to the floor is equal to The figure shows force P pushing crate W along the horizontal plane. The force is pointing downward and to the left, making an angle of theta with the horizontal. P+W 0 Pcos(θ) Psin(θ) Pcos(θ)+W

Pcos(θ)

A 10-kg rock and 20-kg rock are dropped from the same height and experience no significant air resistance. If it takes the 20-kg rock a time T to reach the ground, what time will it take the 10-kg rock to reach the ground? 4T 2T T/2 T/4 T

T

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? The figure shows a box of 10 newtons, which lies on a horizontal tabletop and is connected to the vertically suspended box of 30 newtons by a rope going over a pulley set at the right edge of the tabletop. T = 20 N T > 30 N T = 30 N T = 10 N T < 30 N

T < 30 N

Under what condition is average velocity equal to the average of the object's initial and final velocity? This can only occur if there is no acceleration. The acceleration is constant. This can occur only when the velocity is zero. The acceleration must be constantly increasing. The acceleration must be constantly decreasing.

The acceleration is constant.

A rock from a volcanic eruption is launched straight up into the air with no appreciable air resistance. Which one of the following statements about this rock while it is in the air is correct? On the way down, both its velocity and acceleration are downward, and at the highest point both its velocity and acceleration are zero. The acceleration is downward at all points in the motion except that is zero at the highest point. Throughout the motion, the acceleration is downward, and the velocity is always in the same direction as the acceleration. On the way up, its acceleration is downward and its velocity is upward, and at the highest point both its velocity and acceleration are zero. The acceleration is downward at all points in the motion.

The acceleration is downward at all points in the motion.

A 5-kg ball collides inelastically head-on with a 10-kg ball, which is initially stationary. Which of the following statements is true? (There could be more than one correct choice.) Check all that apply. The magnitude of the change of velocity the 5-kg ball experiences is greater than that of the 10-kg ball. Both balls lose all their momentum since the collision is inelastic. The magnitude of the change of velocity the 5-kg ball experiences is equal to that of the 10-kg ball. The magnitude of the change of the momentum of the 5-kg ball is equal to the magnitude of the change of momentum of the 10-kg ball. The magnitude of the change of velocity the 5-kg ball experiences is less than that of the 10-kg ball.

The magnitude of the change of velocity the 5-kg ball experiences is greater than that of the 10-kg ball. The magnitude of the change of the momentum of the 5-kg ball is equal to the magnitude of the change of momentum of the 10-kg ball.

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. Two graphs for velocities of a truck and a car as functions of time are shown on the same set of axes. The velocity of the truck is positive and remains constant. The velocity of the car increases linearly from the origin and crosses the plot for the truck in a point with coordinate T on the x-axis. At time T, what is true of the distances traveled by the vehicles since time t = 0? The truck will have travelled further than the car. The car will have travelled further than the truck. They will have traveled the same distance. The truck will not have moved.

The truck will have travelled further than the car.

Two objects have masses m and 5m, respectively. They both are placed side by side on a frictionless inclined ramp and allowed to slide down from rest without any air resistance. Which one of the following statements about these objects is correct? It takes the heavier object 10 times longer to reach the bottom of the ramp than the lighter. The two objects reach the bottom of the ramp at exactly the same time. It takes the lighter object 10 times longer to reach the bottom of the ramp than the heavier. It takes the heavier object 5 times longer to reach the bottom of the ramp than the lighter. It takes the lighter object 5 times longer to reach the bottom of the ramp than the heavier.

The two objects reach the bottom of the ramp at exactly the same time.

If the force on an object is in the negative direction, the work it does on the object must be negative. positive. The work could be either positive or negative, depending on the direction the object moves.

The work could be either positive or negative, depending on the direction the object moves.

You are standing in a moving bus, facing forward, when you suddenly slide forward as the bus comes to an immediate stop. What force caused you to slide forward? gravity the normal force due to your contact with the floor of the bus the force due to friction between you and the floor of the bus There is not a force causing you to slide forward.

There is not a force causing you to slide forward.

In an air-free chamber, a pebble is thrown horizontally, and at the same instant a second pebble is dropped from the same height. Compare the times of fall of the two pebbles. They hit at the same time. The dropped pebble hits first. The thrown pebble hits first. We cannot tell without knowing which pebble is heavier.

They hit at the same time.

In a collision between two unequal masses, which mass receives a greater magnitude impulse? the larger mass the smaller mass They receive equal impulses.

They receive equal impulses.

Inside of a train a ball of weight W is hanging by a light wire at rest from the ceiling. The wire makes an angle θ with the ceiling, as shown in the figure. Which one of the following conditions must be true about the tension T in the wire? The figure shows a ball being hanged by a wire from the ceiling. The wire makes an acute angle theta with the horizontal. T=ma Tcos(θ)=W Tsin(θ)=W T=W Ttan(θ)=W

Tsin(θ)=W

A 10-kg rock and a 20-kg rock are dropped at the same time and experience no significant air resistance. If the 10-kg rock falls with acceleration a, what is the acceleration of the 20-kg rock? 2a a/2 4a a/4 a

a

The total mechanical energy of a simple harmonic oscillating system is a minimum when it passes through the equilibrium point. a maximum when it passes through the equilibrium point. zero when it reaches the maximum displacement. a non-zero constant. zero as it passes the equilibrium point.

a non-zero constant.

An object is moving with constant non-zero acceleration in the +x direction. The position versus time graph of this object is a horizontal straight line. a vertical straight line. a straight line making an angle with the time axis. a parabolic curve.

a parabolic curve.

An object is moving with constant non-zero velocity in the +x direction. The position versus time graph of this object is a horizontal straight line a vertical straight line. a straight line making an angle with the time axis. a parabolic curve.

a straight line making an angle with the time axis.

The slope of a velocity versus time graph gives velocity. acceleration. displacement. the distance traveled.

acceleration.

A 75-N box rests on a perfectly smooth horizontal surface. The minimum force need to start the box moving is 750 N. 75 N. 7.5 N. any horizontal force greater than zero.

any horizontal force greater than zero.

If the position versus time graph of an object is a horizontal line, the object is moving with constant non-zero speed. moving with constant non-zero acceleration. at rest. moving with increasing speed.

at rest.

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 be directly over the package. be behind the package. depend on the speed of the plane when the package was released. be in front of the package.

be directly over the package.

The motion of a particle is described in the velocity vs. time graph shown in the figure. The plot shows the velocity of a particle as function of time. Time is measured from 0 to 9.0 seconds on the x-axis. The velocity is measured from -4.0 to 5.0 meters per second on the y-axis. The velocity increases linearly from 0 seconds and -2.5 meters per second to 9.0 seconds and 3.5 meters per second. Over the nine-second interval shown, we can say that the speed of the particle only decreases. decreases and then increases. remains constant. increases and then decreases. only increases.

decreases and then increases.

The area under a curve in a velocity versus time graph gives displacement. acceleration. position. velocity.

displacement.

A simple harmonic oscillator oscillates with frequency f when its amplitude is A. If the amplitude is now doubled to 2A, what is the new frequency? f f/4 4f 2f f/2

f

A block of mass m sits at rest on a rough inclined ramp that makes an angle θ with the horizontal. What must be true about force of static friction f on the block? f > mgsin(θ) f > mgcos(θ) f = mgcos(θ) f > mg f = mgsin(θ)

f = mgsin(θ)

A 10-kg rock and a 20-kg rock are thrown upward with the same initial speed v0 and experience no significant air resistance. If the 10-kg rock reaches a maximum height h, what maximum height will the 20-kg ball reach? 4h h/4 2h h h/2

h

You are trying to cross a river that flows toward the south with a strong current. You start out in your motorboat on the east bank desiring to reach the west bank directly west from your starting point. You should head your motorboat directly toward the west. in a general northwesterly direction. directly toward the north. in a general southwesterly direction.

in a general northwesterly direction.

The momentum of an isolated system is conserved only in elastic collisions. in both elastic and inelastic collisions. only in inelastic collisions.

in both elastic and inelastic collisions.

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

is always zero.

Two boxes P and Q on a perfectly smooth horizontal surface are connected by a light horizontal cord. The mass of P is greater than that of Q. A horizontal force F is applied to box 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 is zero. greater than F. less than F but not zero. equal to F.

less than F but not zero.

A person who normally weighs 700 N is riding in an elevator that is moving upward but slowing down at a steady rate. If this person is standing on a bathroom scale inside the elevator, what would the scale read? 700 N less than 700 N more than 700 N It could be more or less than 700 N, depending on whether the magnitude of the acceleration is greater than or less than 9.8 m/s2.

less then 700 N

If the velocity versus time graph of an object is a horizontal line, the object is moving with zero acceleration. moving with constant non-zero acceleration. at rest. moving with increasing speed.

moving with zero acceleration.

A player kicks a soccer ball in a high arc toward the opponent's goal. At the highest point in its trajectory the ball's acceleration is zero but its velocity is not zero. both the velocity and the acceleration of the soccer ball are zero. the ball's velocity points downward. neither the ball's velocity nor its acceleration are zero. the ball's acceleration points upward.

neither the ball's velocity nor its acceleration are zero.

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? tangent to the curve in the forward direction perpendicular to the curve outward 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

Two forces produce equal torques on a door about the door hinge. The first force is applied at the midpoint of the door; the second force is applied at the doorknob. Both forces are applied perpendicular to the door. Which force has a greater magnitude? the second force (at the doorknob) the first force (at the midpoint) The two forces are equal.

the first force (at the midpoint)

You push on box G that is next to box H, causing both boxes to slide along the floor, as shown in the figure. The reaction force to your push is The figure shows two rectangular boxes, labeled G and H, lying back to back on a horizontal surface. Box H is to the right of box G. Box H is higher than box G. Force is applied to box G horizontally to the right. the upward force of the floor on box G. the push of box G on box H. the acceleration of box G. the push of box G against you. the push of box H on box G.

the push of box G against you.

From the edge of a roof top you toss a green ball upwards with initial speed v0 and a blue ball downwards with the same initial speed. Air resistance is negligible. When they reach the ground below the blue ball will be moving faster than the green ball. the two balls will have the same speed. the green ball will be moving faster than the blue ball.

the two balls will have the same speed.

The slope of a position versus time graph gives displacement. velocity. acceleration. the distance traveled.

velocity.

In simple harmonic motion, when is the speed the greatest? (There could be more than one correct choice.) Check all that apply. when the magnitude of the acceleration is a minimum when the potential energy is a maximum when the magnitude of the acceleration is a maximum when the displacement is a maximum when the potential energy is a zero

when the magnitude of the acceleration is a minimum when the potential energy is a zero

When is the average velocity of an object equal to the instantaneous velocity? always only when the velocity is decreasing at a constant rate when the velocity is constant never only when the velocity is increasing at a constant rate

when the velocity is constant

Suppose that an object travels from one point in space to another. Make a comparison between the magnitude of the displacement and the distance traveled by this object. The displacement is either greater than or equal to the distance traveled. The displacement is always equal to the distance traveled. The displacement is either less than or equal to the distance traveled. The displacement can be either greater than, smaller than, or equal to the distance traveled.

The displacement is either less than or equal to the distance traveled.

A fireman is sliding down a fire pole. As he speeds up, he tightens his grip on the pole, thus increasing the vertical frictional force that the pole exerts on the fireman. When the force on his hands equals his weight, what happens to the fireman? The acceleration of the fireman is now upward. The fireman comes to a stop. The fireman descends with slower and slower speed. The fireman continues to descend, but with constant speed. The fireman descends with a smaller but non-zero acceleration.

The fireman continues to descend, but with constant speed.

Which of the following statements are true about an object in two-dimensional projectile motion with no air resistance? (There could be more than one correct choice.) The acceleration of the object is zero at its highest point. The horizontal acceleration is always zero and the vertical acceleration is always a non-zero constant downward. The speed of the object is constant but its velocity is not constant. The speed of the object is zero at its highest point. The acceleration of the object is +g when the object is rising and -g when it is falling.

The horizontal acceleration is always zero and the vertical acceleration is always a non-zero constant downward.

An object is moving with constant non-zero velocity. Which of the following statements about it must be true? A constant force is being applied to it in the direction opposite of motion. A constant force is being applied to it perpendicular to the direction of motion. A constant force is being applied to it in the direction of motion. The net force on the object is zero. Its acceleration is in the same direction as it velocity.

The net force on the object is zero.

If the units of your answer are kg • m2/s3, which of the following types of quantities could your answer be? (There could be more than one correct choice.) force work kinetic energy potential energy power

power

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

remains a non-zero constant.

You are in a train traveling on a horizontal track and notice that a piece of luggage starts to slide directly toward the front of the train. From this observation, you can conclude that this train is changing direction. speeding up. slowing down. speeding up and changing direction. slowing down and changing direction.

slowing down.

Two friends are standing on opposite ends of a canoe that is initially at rest with respect to a frictionless lake. The person in the front throws a very massive ball toward the back, and the person in the back catches it. After the ball is caught, the canoe is moving forward. moving backward. stationary.

stationary.

A ball is thrown horizontally from the top of a tower at the same instant that a stone is dropped vertically. Which object is traveling faster when it hits the level ground below if neither of them experiences any air resistance? It is impossible to tell because we do not know their masses. the stone the ball Both are traveling at the same speed.

the ball