### VectorS & Relative Motion

```Vectors &
Relative Motion
Multiple-Choice Practice
Problems
Question #1
In a diagram, the length of a
vector arrow represents the
a) type of vector.
b) direction of the vector.
c) magnitude of the vector.
d) cause of the vector.
Question #2
Which of the following quantities
used to describe motion is an
example of a vector quantity?
a) distance
b) speed
c) time
d) average velocity
Question #3
A vector remains unchanged
a) if it is moved in any direction.
b) only if it is moved parallel to its
original direction.
c) only if it is rotated perpendicular
to its original direction.
d) only if it is not moved.
d.
only if it
Refer to the figure below to answer the following questions.
Question #4
Which 4.ofWhich
these
displacements
of the displacements,
order given, will yield a displacement equal to
will be equal
d1 +d2 +d3?
d + d + d to
?
a. d + d + d
a) d3+d4+d1
b. d + d + d
c. d + d + d
d. d + d + d
b) d2+d1+d3
c) d2+d4+d3
d) d4+d3+d1
1
2
3
3
4
1
2
1
3
2
4
3
4
3
1
5. Which of the
resulting in th
vectors d2 -d1
a.
b.
c.
d.
d.
ing questions.
only if it
Refer to the figure below to answer the following questions.
Question #5
he displacements, when added in the
5. Which of the following represents th
, will yield a displacement equal to
resulting in the subtraction of the dis
vectors d2 -d1 shown in the figure?
3?
+ d1
a.
+ d3
Which of
the following represents the 5. Which of the
4. Which of the displacements, when added in the
e+ d3
5. Whichresulting
oforder
the given,
following
represents
the
will
a displacement
equalvector
to
resulting in th
vector
in yield
the
subtraction
of
d1 +the
d2 + subtraction
d3 ?
vectors d2 -d1
+ d1
resulting in
of the displacement
d2 vectors
−d1 shown
din
+ dthe figure?
d2a. -dd1 +shown
in the figure?
3
a.
b.
c.
d.
4
1
d2 + d1 + d3
d2 + d4 + d3
d4 + d3 + d1
b.
c.
b.
a.
d.
b.
c.
d.
Question #7
If vectors are moved according to the rules of
the triangle method of vector addition, then
the resultant vector is drawn
a) from the tail of the first vector to the tail of
the last vector.
b) from the tail of the first vector to the tip of
the last vector.
c) from the tip of the first vector to the tail of
the last vector.
d) from the tip of the first vector to the tip of
the last vector.
Question #8
A skier slides onto a horizontal patch of
slushy snow at velocity vskier, and slows
to a constant speed without changing
direction. Which of the following could
be the skier’s resulting velocity?
a) -3vskier
b) +(1/4) vskier
c) -(1/5) vskier
d) all of the above.
Question #11
In a school playground, a child runs 5 m in
the x direction and then 2.0 m in the –y
direction. Which of the following represents
the magnitude of the child’s displacement?
Question #12
In the triangle below, what does Θequal?
Question #13
The projection of a vector along
the axes of a coordinate system is
a) a component of the vector.
b) a tangent of the vector.
c) the resultant of the vector.
d) the magnitude of the vector.
Question #14
The components of a vector are
a) each equal to half the
magnitude of the vector.
b) independent of the
orientation of the vector.
c) perpendicular.
d) vector quantities.
Question #15
A vector that has components that lie
along the -x-axis and the +y-axis is
oriented at angle A measured
counterclockwise from the +x-axis. Which
of these ranges gives values of A?
a) 0°<A<90°
b) 90°<A<180°
c) 180°<A<270°
d) 270°<A<360°
Question #16
If the x-component of B equals
the magnitude of B, then
a) both components are equal.
b) By equals B2+Bx2
c) By equals zero.
d) By lies along the y-axis.
Question #17
Which of the following is a frame
of reference for measuring
motion?
a) coordinate system
b) diagram
c) graph
d) none of the above
Question #18-22 Story
In a circus parade, a clown
standing on a float moving at a
constant forward speed drops a
fake dumbbell. A child in the
bleachers on the sidewalk
observes the dumbbell falling.
Question #18
Who would observe the dumbbell
falling straight down?
a) The clown only
b) The child only
c) The clown and the child
d) Neither
Question #19
Who would observe the dumbbell
falling backward?
a) The clown only
b) The child only
c) The clown and the child
d) Neither
Question #20
The clown and child would agree
a) The time for the dumbbell to fall
b) The distance the dumbbell falls
c) The initial velocity of the
dumbbell
d) All of the above
Question #22
If the float has a velocity of +vfloat
with respect to the ground, what is
the velocity of the child with respect
to the clown?
a) 0
b) +vfloat
c) -vfloat
d) (+vfloat –vchild)/2
Question #23
The velocity of a passenger relative to a
boat is -vpb. The velocity of the boat relative
to the river is +vbr. The velocity of the river to
the shore is +vrs. What is the velocity of the
passenger relative to the shore?
a) -vpb+vbr +vrs
b) vpb - (vbr + vrs)
c) -(vpb + vbr + vrs)
d) vpb+vbr+vrs
Question #24
A car traveling at the speed limit has
velocity +vcar with respect to the road. You
are in another car traveling in the opposite
direction at the speed limit with respect to
the road. As the first car approaches you,
what is its velocity relative to you?
a) +vcar
b) vcar
c) +2vcar
d) -2vcar
1:
C
2: D
3: B
4: B
5: D
7: B
8: B
11:
D
12: A
13: A
14: C
15: B
16: C
17: A
18:
A
19: D
20: D
21: C
22: B
23: A
24: C
```