Read p.63­68
In notes:
Define/explain/or give examples in notes: graphical representation of vectors
algebraic representation of vectors
resultant vector
relative velocity
A vector is graphically represented
by an arrow. The length of the arrow corresponds with the magnitude(size) of the vector. The direction of the arrow indicates the direction of the vector quantity the arrow represents.
Algebraically, a vector is represented by a letter symbol with an arrow over top of it. for example, a velocity can be represented by: v
A resultant vector is the vector sum of two or more vectors
Relative velocity of a moving object is that object's velocity as compared to another object or setting. We typically use the surface of the Earth as reference to measure objects' velocity
Draw an example of adding two vectors graphically, draw and label the resultant.
Draw a right triangle with leg sides equal to 10 m and 26 m. Use Pythagorean theorem to determine the length of the hypotenuse. Use tan­1 to determine the two unknown angles of this triangle.
P.67 do practice problems 1 & 2 draw a neat labeled vector diagram, similar to 4­3 on p. 65 a Vector is represented by an arrow!
Head
tail
Head wind and Tail wind
A Rhinebeck Aerodrome plane flies
with an airspeed of 120 km/hr into a
headwind of 50 km/hr blowing east.
What is the plane's resultant velocity?
( How fast will it appear to be flying from
someone's point of view on the ground below?)
wind
Upstream ­­­downstream
Resultant? what's it mean?
A resultant is a vector sum of two or more vectors.
Resultant
A + B
vector A
vector B
vector D
vector C
vector E
Resultant
C + D + E
A crew boat rowing with a water velocity of 4.0 m/s relative to the water is headed upstream in a river that has a water current of 1.5 m/s.
What is the boat's resultant velocity with respect to the shore?
river
current
river
bank
1.5 m/s
4.0 m/s
Boat's resultant
velocity
2.5 m/s
4.0 m/s
1.5 m/s
bank
Mr. Vining heads out for a rock hunt and travels 12 miles West, the turns and heads 5 miles North.
What's his resultant displacement?
magnitude
of displacement
13 miles
5 miles
angle
angle = tan­1
12 miles
So, Mr. Vining's resultant displacement
was 13 miles 23° North of West
(note: it would be ok to say 67° West of North)
(
= 23 °
(
5 miles
_______
12 miles
An airplane is flying West with an airspeed of 300 mi/hr into a head wind of 110 mi/hr.
What is the plane's resultant velocity as seen from the ground? answer:
190 km/hr, West
note: direction is important to state since velocity is vector
Showing Vectors added that are not in the same direction.......
Head to tail diagrams
vector 1 + vector 2 = Resultant
vector 1
vector 2
Tail to tail diagrams (parallelogram method)
vector 1 + vector 2 = Resultant
vector 1
nt
a
ult
2
s
Re
you must draw
parallel "guidelines"
su
2
Re
you must draw
parallel "guidelines"
lta
nt
vector 1
vector 1
Resu
lt
2
ant
you must draw
parallel "guidelines"
Draw a head to tail resultant
20 m
12 m
resultant
4 m
14 m
Head to Tail!
Tail to Tail ( construct a parallelogram)