AP Physics Semester final – Flashcards

if an object is in uniform motion, the dots on motion diagrams

Making rough estimates of physical quantities is useful

What is the difference between speed and velocity?

The quantity 2.67 × 103 m/s has how many significant figures?

The correct SI units for distance and mass are _____ and _____.

Velocity vectors point __________.

If Sam walks 100 m to the right, then 200 m to the left, his net displacement vector __________.

The video showed two clips of a cyclist moving along a stretch of pavement. In each clip,

If you throw a ball against the ceiling—so the ball moves upward and then rebounds to move downward—at the instant the ball hits the ceiling, the acceleration is

Consider two graphs of velocity versus time for two objects in free fall. What can we say about the graphs? A. The two graphs have the same slope. B. The two graphs are both straight lines. C. both are true

The slope at a point on a position-versus-time graph of an object is the __________.

Which of the following is an example of uniform motion 1. A person at rest starts running in a straight line in a fixed direction 2. A car going around a circular track at a constant speed 3. A ball dropped from the top of a building 4. A hockey puck sliding in a straight line at a constant speed

The area under a velocity-versus-time graph of an object is __________.

If an object is speeding up, __________. 1. its acceleration can be positive or negative depending on the direction of motion 2. its acceleration is positive 3. its acceleration is negative

A 1-pound ball and a 100-pound ball are dropped from a height of 10 feet at the same time. In the absence of air resistance, __________. 1. the 1-pound ball wins the race 2.There's not enough information to determine which ball wins the race. 3. the 100-pound ball wins the race 4. the two balls end in a tie

The slope at a point on a position-versus-time graph of an object is

You toss a basketball toward the basket. At the highest point of its arc, 1. The vertical component of the velocity is zero. 2. The horizontal component of the velocity is zero. 3. Both the horizontal and vertical components of the velocity are zero.

An object in circular motion has velocity that is constantly changing. The direction of the acceleration is 1. Parallel to the motion, along the circle. 2. Away from the center of the circle. 3. Toward the center of the circle.

The video showed examples of vector operations on which two vector quantities? 1. Acceleration and force 2. Displacement and acceleration 3. Velocity and force 4. Velocity and acceleration 5. Displacement and velocity

The ______ of a vector is always a positive quantity. 1. magnitude 2.direction 3. X-component 4. Y-component

Ax is positive if is directed _______; Ay is positive if is directed _______. 1. right / up 2. right / down 3. left / up

The acceleration of a cart rolling down a ramp depends on __________. 1. both the angle of the ramp and the length of the ramp 2. neither the angle of the ramp or the length of the ramp 3. the angle of the ramp 4. the length of the ramp

The acceleration vector of a particle in projectile motion ________. 1. Is directed down at all times. 2. Points along the path of the particle. 3. Is directed horizontally. 4. Vanishes at the particle's highest point.

The acceleration vector of a particle in uniform circular motion __________. 1. is zero 2. points toward the center of the circle 3. points tangent to the circle, in the direction of motion 4. points tangent to the circle, opposite the direction of motion

The acceleration that an object experiences is 1. Inversely proportional to the net force, proportional to the mass. 2. Inversely proportional to the net force, inversely proportional to the mass. 3. Proportional to the net force, proportional to the mass. 4. Proportional to the net force, inversely proportional to the mass.

The names for the two types of friction discussed in the video are 1. Rolling friction and kinetic friction. 2.Static friction and sliding friction. 3. Kinetic friction and potential friction. 4. Static friction and kinetic friction. 5. Dynamic friction and static.

If you are not wearing a seat belt and the car you are driving hits a fixed barrier, you will hit the steering wheel with some force. This is because __________. 1. the force of the collision has thrown you forward 2. the steering wheel has been pushed back toward you 3. you continue moving even after the car has stopped

If you stand on a trampoline, it depresses under your weight. When you stand on a hard stone floor, __________. 1. the floor deforms a slight amount if you are heavy enough 2. the floor does not deform under your weight; it is too stiff 3. the floor deforms—very slightly—under your weight

Which of these is NOT a force discussed in this chapter? 1. the thrust force 2. the normal force 3. the orthogonal force 4. the tension force

If you are standing on the floor, motionless, what are the forces that act on you? 1. weight force and normal force 2. normal force and friction force 3. weight force

A skydiver has reached terminal velocity—she now falls at a constant speed, so her acceleration is zero. Is there a net force on her? If so, what is the direction? 1. There is no net force. 2. There is a net force directed upward. 3. There is a net force directed downward.

An action/reaction pair of forces ____________. 1. points in the same direction. 2. acts on the same object. 3. acts on two different objects. 4. are always long-range forces.

The two different types of equilibrium discussed in the video are 1. Static equilibrium and dynamic equilibrium 2. Potential equilibrium and kinetic equilibrium 3. Dynamic equilibrium and kinematic equilibrium 4. Kinetic equilibrium and static equilibrium

If you experience weightlessness, this means that 1. There is no net force acting on you. 2. You are accelerating upward. 3. Your apparent weight is zero. 4. There is no gravity acting on you.

For the block sliding on the table in the video, the force of kinetic friction was __________ the maximum value of the static friction force; this is generally true. 1. Smaller than 2. The same as 3. Larger than

Which of these objects is in equilibrium? 1. A car driving down the road at a constant speed. 2. A skydiver falling at a constant speed. 3. A block sitting at rest on a table. 4. All of the listed answers are correct.

You are riding in an elevator that is accelerating upward. Suppose you stand on a scale. The reading on the scale is __________. 1. greater than your true weight 2. less than your true weight 3. equal to your true weight

In general, the coefficient of static friction is __________. 1. smaller than the coefficient of kinetic friction 2. equal to the coefficient of kinetic friction 3. greater than the coefficient of kinetic friction

The drag force pushes opposite your motion as you ride a bicycle. If you double your speed, what happens to the magnitude of the drag force? 1. The drag force increases. 2. The drag force decreases. 3. The drag force stays the same.

Two boxes are suspended from a rope over a pulley. Each box has weight 50 N. What is the tension in the rope? 1. 25 N 2. 50 N 3. 100 N

For an object in uniform circular motion, what can you say about the directions of the velocity, acceleration, and net force vectors? 1. The velocity vector is perpendicular to the acceleration vector; the acceleration vector is perpendicular to the net force vector. 2. The velocity vector is perpendicular to the acceleration vector; the acceleration vector is parallel to the net force vector. 3. The velocity vector is parallel to the acceleration vector; the acceleration vector is parallel to the net force vector. 4. The velocity vector is parallel to the acceleration vector; the acceleration vector is perpendicular to the net force vector.

In the video, a car rounding a corner and a car going over the crest of a hill are both presented as examples of 1. Uniform circular motion. 2. Apparent weight making passengers "feel heavy." 3. Acceleration produced by a net force parallel to the velocity. 4. Acceleration produced by friction forces.

Astronauts on the International Space Station feel weightless because 1. They are far enough above the earth's surface that the gravitational force is negligible. 2. They are above the earth's atmosphere. 3. Their apparent weight is zero. 4. The gravity of the earth and the sun are directed opposite each other, so there is no net gravitational force.

How many times per day does the International Space Station—or any satellite in a similar low orbit—go around the earth? 1 3 5 15

Newton's law of gravity describes the gravitational force between __________. 1. All of the listed answers are correct. 2. Earth and the moon. 3. a person and the earth. 4. Earth and the sun. 5. the sun and the planets.

For uniform circular motion, the acceleration __________. 1. is always due to gravity 2. is parallel to the velocity 3. is larger for a larger orbit at the same speed 4. is directed toward the center of the circle

When a car turns a corner on a level road, which force provides the necessary centripetal acceleration? 1. friction 2. tension 3. gravity 4. normal force 5. air resistance

In the video, the two stuffed animals that rode on the turntable had the same __________ but had different __________. 1. Angular velocity, velocity 2. Velocity, angular velocity 3. Velocity, acceleration 4. Acceleration, velocity

When we draw a diagram of the forces acting on an extended object, the tail of the force vector for the weight should be at 1. The object's center of gravity. 2. The object's moment of inertia. 3. The object's center. 4. The object's center of rotation.

In the video, we looked at the problem of balancing a pencil on your fingertip, which is easy for a long pencil, hard for a short pencil. If you consider a long and a short pencil tipped to the side, the __________ of the shorter pencil is larger. 1. Moment of inertia 2. Angular acceleration 3. Center of mass 4. Torque

A net torque applied to an object causes __________. 1. the object to rotate at a constant rate 2. the angular velocity of the object to change 3. the moment of inertia of the object to change 4. a linear acceleration of the object

If an object is rotating clockwise, this corresponds to a _____ angular velocity. 1. positive 2. negative

Moment of inertia is 1. the rotational equivalent of mass. 2. the point at which all forces appear to act. 3. the time at which inertia occurs. 4. an alternative term for moment arm.

Which factor does the torque on an object NOT depend on? 1. the magnitude of the applied force 2. the angle at which the force is applied 3. the object's angular velocity

If you kick a ball, you apply an impulse. The impulse is equal to 1. The momentum of your foot. 2. The maximum force between your foot and the ball. 3. The change in momentum of the ball. 4. The momentum of the ball.

When we say that momentum is "conserved," we mean 1. The momentum of an isolated system is constant. 2. The momentum of the universe increases; it never decreases. 3. If there are no forces acting on an object, its momentum is zero. 4. The momentum of an object is the same before and after a collision.

The total momentum of a system is conserved __________. 1. if no internal forces act on the system always 2. never; it's just an approximation 3. if no external forces act on the system

An object's angular momentum is proportional to its __________. 1. moment of inertia 2. linear momentum 3. kinetic energy 4. mass

In an inelastic collision, 1. momentum is conserved 2. energy is conserved 3. force is conserved 4. impulse is conserved 5. elasticity is conserved

Impulse is ________. 1. the area under the force curve in a force-versus-time graph. 2. a force that is applied very suddenly. 3. the time interval that a force lasts. 4. a force that is applied at a random time.