AP Physics Semester Review

What must be true about the force of static friction f on the block?

f=mg sin(theta)

If a vector's components are all negative then the magnitude of the vector is negative

False

A projectile is launched with an initial velocity of 80 m/s at 30 above the horizontal. Neglecting air, what is the horizontal component of the projectile's acceleration?

0 m/s

What should the value of the first tick-mark on the vertical scale, as indicated by the arrow in the figure?

100

A plane flying horizontally at a speed if 50 m/s and an elevation of 160m drops a package and 2s later it drops a second package. How far apart will the two packages land on the ground if airless?

100m

If the mass of object 2 is 36kg what are the masses of objects 1 and 3?

12kg and 90kg

A projectile is fired from ground level with a speed of 150 m/s at an angle of 30 above the horizontal on an airless planet where g= 10 m/s^2. What is the horizontal component of its velocity after 4s?

130 m/s

What is the magnitude of the force that the surface of the hill exerts on the sled?

160 N

If 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

If 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

The horizontal and vertical components of the initial velocity of a football are 16 m/s and 20 m/s. How long does it take the football ti reach the top of its trajectory

2s.

What is the mass of an object that experiences a gravitational force of 351N near Earth's surface where g=9.8 m/s^2?

35.8kg

At value of t is the speed of the particle equal 0 m/s?

3s

When Jeff ran up a hill at 7 m/s the horizontal component of his velocity vector was 5.1, what was the vertical component of Jeff's velocity

4.8 m/s

If I weigh 876N on earth at a place where g= 9.8 m/s^2 and 5320N on the surface of another planet, what is the acceleration due to gravity on that planet?

59.5

A person is using a rope to lower a 5N bucket into a well with a constant speed of 2 m/s. What is the magnitude of the force exerted but he rope on the bucket?

5N

A truck is using a hook to tow a car whose mass is one quarter that of the truck. If the force exerted by the truck on the car is 6000 N then the force exerted by the car on the truck is

6000N

A person who normally weighs 700N is riding in a rather swift elevator that is moving at a constant speed of 9.8 m/s. If the person is standing on a bathroom scale inside the elevator, what would the scale read?

700N

When rolled down a mountain side a 7 m/s, the horizontal component of its velocity vector was 1.8 m/s. What was the angle of the mountain surface above the horizontal?

75

A ball is thrown at an original speed of 8 m/s at an angle of 35 above the horizontal. If there is no air resistance, what is the speed of the ball when it returns to the same horizontal level

8 m/s

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

90 to 180

A stone is thrown horizontally with an initial speed of 10 m/s from the edge of a cliff. A stopwatch measures the stone's trajectory time from the top of the cliff to the bottom to be 4.3 s. What is the height of the cliff if the air resistance is negligibly small?

91m

If the 10-kg rock falls with acceleration A, what is the acceleration of the 20-kg rock?

A

Which of the following below shows a correct free-body diagram of the horizontal forces acting on the lower block, B?

A. 100N <---B---> 100N

Which of the following graphs represent an object at rest?

A. position vs time graph straight line and above the x-axis

Which of the following situations is impossible?

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

Which of graphs shown below best represents the acceleration of the stone as a function of time?

B. straight and below the x-axis

Shown below are the velocity and acceleration vectors for an object in several different types of motion. In which case is the object slowing down and turning to its right?

B. vector a is up and to the left and vector v is straight down

Where on the track was the car when it was traveling at half this speed, this is at 70km/hr?

Before marker 1

Consider two vectors A and B shown. The difference between A-B is best illustrated by

C

Which graph shown below best represents the velocity of the stone as a function of time?

C. (shortest straight line)

Which of the following free-body diagrams most realisticly represents the forces acting on the two objects in the moving system

D. equal M. larger line on top for m

A block of mass m sits at rest on a rough inclined ramp that makes an angle theta with the horizontal. What must be true about normal force F on the block due to the ramp?

F= mg cos(theta)

In a collision between a huge suv and a small hybrid car, the SUV exerts a larger force on the hybrid than the hybrid exerts of the SUV

False

If the 10-kg rock reaches a maximum height H, what maximum height will the 20-kg ball reach?

H

8b. At which moment in time is the speed of the object equal to zero?

I

Which statement concerning its acceleration must be correct?

It acceleration is in the -x direction

8a. At which moment in time is the speed of the object the greatest?

J

The frictional force on the box due to the floor is equal to

P cos(theta)

If it takes the 20-kg rock time T to reach the ground, what time will it take the 10-kg rock to reach the ground?

T

What is true about the tension T in the string?

T < 30N

which one of the following conditions must be true about the tension T in the wire?

T sin(theta) = W

Which of the following statements about tension is correct

T1 > T2

According to this graph, which statements about these cars must be true?

The cars meet at t=10s. Both cars have the same acceleration.

If you pound a feather with a hammer, which one feels a greater force?

The size of the force is exactly the same

At the time T, what is true of the distances traveled by the vehicles since time t=0?

The truck will have traveled further than the car

The normal force on the box die to the floor is equal to

W + P sin(theta)

The slope of a velocity vs time graph gives

acceleration

If the position vs time graph of an object is a horizontal line, the object is

at rest

In the figure what does the spring scale read?

exactly 1 N

Two displacement vectors have magnitudes of 5 and 7. If these two vectors are added together, the magnitude of the sum

could be as small as 2 or as large as 12

Over the nine-second interval shown, we can say that the speed of the particle

decreases then increases

The area under the curve in a velocity versus time graph gives?

displacement

Which of the following graphs represent an object having zero acceleration?

graphs A and B

When a ball is thrown straight up with no air resistance, the acceleration at its highest point

is downward

An object in the +x direction experiences an acceleration of 2 m/s^2. This means the object

is increasing its velocity by 2 m/s every second

The magnitude of the force that the boxes exert on each other is

larger if F is applied toward the left

The magnitude of the force exerted by the connecting cord on body P is

less than F but not zero

You are in a train traveling on a horizontal track ad 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

slowing down

You push on box G that is next ti H causing both boxes to slide along the floor. The reaction force to your push is

the push of box G against you

The slope of a position vs time graph gives

velocity