Day One
AP Physics C Fall 2016 1st trimester Notes #1
(What is a vector? Know what physics quantities are vectors. AP
multiple choice questions do ask this!)Vectors: Getting pointed in
the correct direction!Chapter Three
1. What is a vector?
a. Which of the following are vectors?
TimeDistanceDisplacementSpeedVelocity
AccelerationForceWorkTorqueNormal Force
Frictional forcePowerPotential energyCapacitanceMomentum
Adding parallel Vectors
2. The magnitudes of displacements a and b are 3m and 4m,
respectively, and c=a+b. Considering various orientations of a and
b, what is
(a) the maximum possible magnitude for c?
(b) the minimum possible magnitude for c?
3. Adding perpendicular vectors graphically.
(Know how to add parallel vectors Know how to add perpendicular
vectors graphically and algebraically )
Perpendicular vectors
4. A wheel with a radius of 0.45 m rolls without slipping along
a horizontal floor. At time t1, the dot P painted on the rim of the
wheel is at the point of contact between the wheel and the floor.
At a later time t2, the wheel has rolled through one-half of a
revolution. What are the magnitude and the angle (relative to the
floor) of the displacement of P?
(Know the difference between distance and displacement)
5. A room has dimensions 3 m (height) x 3.7 m x 4.3 m. A fly
starting at one corner flies around, ending up at the diagonally
opposite corner.
a. What is the magnitude of its displacement?
a. Could the length of its path be less than this magnitude?
b. Greater than this magnitude?
c. Equal to this magnitude?
6. An object having an initial momentum that may be represented
by the vector above strikes an object that is initially at rest.
Which of the following sets of vectors may represent the momentum
of the two objects after the collision?
(A)
(Be able to add vectors graphically)(B)
(C)
(D)
(E)
(Know how to add vectors using the component method. )Adding
Vectors (Remember the Component Method!)
7. Add the following two velocity vectors. Angles are given from
the positive x axis. Give answer in magnitude/angle notation.
(2 m/s at 3500)
(5 m/s at 1200)
(Find the components of a vector written in magnitude direction
notation )
Unit Vector Notation (components)
8. What is a unit vector?
(Be able to write a quantity in unit vector notation)
a. What does look like? How else could you write this
vector?
b. Write the following in unit vector notation.
9m at -30 degrees
c. How do you convert from radians to degrees?
9.
(Find the magnitude of a vector written in vector
notation)Given
a. What do you know about the path traveled?
b. What do you know about the displacement?
c. What’s the magnitude of the displacement? (won’t ask for
direction of a 3-D vector)
(Be able to add vectors written in unit vector notation)
10.
If and what is in vector notation?
(Be able to find the angle relative to +x for a vector written
in unit vector notation)
In magnitude and angle relative to ?
11. An ant crazed by the sun on a hot Texas afternoon darts over
an xy plane scratched in the dirt. The x and y components of four
consecutive darts are the following, all in centimeters: (30.0,
40.0), (bx, -70.0), (-20.0, cy), (-80.0, -70.0). The overall
displacement of the four darts has the xy components (-140,
-20).
What are components bx and cy?
What are the magnitude and angle of the overall
displacement?
12. (Be able to subtract vectors (graphically and unit vector
notation))Subtracting Vectors
Vectors V1, and V2 shown above have equal magnitudes. The
vectors represent the velocities of an object at times t1, and t2,
respectively. The average acceleration of the object between time
t1 and t2 was
(A) zero (B) directed north (C) directed west (D) directed north
of east (E) directed north of west
13.
If and what is in vector notation?
What is the magnitude? (Again no direction with 3-D vectors)
(Be able to multiply a vector by a scalar)Multiplying
vectors
14. Multiply a vector by a scalar.
a.
What is the resultant force if the following force is
tripled?
15. (Be able to use vector notation to solve a system of
equations)Given that , and find x and y.
(Be able to multiply two vectors for a scalar product
)Multiplying a vector by a vector
16. Scalar product (Dot product- work)
a. How do you draw the vectors to find the angle between
them?
b. What if the vectors are perpendicular? Parallel? What are we
multiplying about the vectors?
17. Vectors C and D have magnitudes of 3 units and 4 units
respectively. What is the angle between the directions of C and D
if C◦D equals
a. zero
b. 12 units
c. -12 units
(B3)
(B4) (B2) (A)
(B1)
18. Above shows vector A and four choices for vector B that
differ only in orientation. Rank the choices according to the
absolute value of , greatest first.
19. (Know how to find the angle between two vectors by using the
dot product rule)How could you determine the angle between two
vectors if you know the components? (Will be on quiz and
homework!!!!)
20. If
21. The constant force F with components Fx= 3N and Fy=4N, acts
on a body while that body has the displacement vector of r= 12mi
–5mj.
a. How much work does the force do on the body during this
displacement? (Work=)
b. What is the magnitude of the force vector?
c. What is the magnitude of the displacement vector?
d. What is the angle between them?
22. (Don’t be “cross” we are back to school! Let’s move quickly
in a positive direction! ) (Know how to multiply two vectors for a
vector product )Vector Product (Cross product )
i.
ii. Matrix method (determinate)
23. Vectors C and D have magnitudes of 3 units and 4 units
respectively. What is the angle between the directions of C and D
if C x D equals
a. zero
b. 12 units
24. If what is the vector product?
25. How do you determine the direction of the final vector?
26.
(Know how to use the cross product with letters instead of
numbers ) You know where q=3 , F= and B=. Find the velocity if
vx=vy.
27. Given the two vectors:
Find (
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