Vectors (Ch. 3) Flashcards
1
Q
scalars
A
- quantities with magnitude only
- eg - time, displacement, speed
2
Q
vectors
A
- quantities with both magnitude and direction
- eg - velocity, displacement, acceleration
3
Q
addition/subtraction of vectors along the same direction
A
- add/subtract like a scalar quantity
4
Q
addition/subtraction of vectors that are perpendicular
A
- use the head-to-tail method
- to add, place the tail of vector 2 at the head of vector 1; the resultant vector is drawn from the tail of vector 1 and ends at the head of vector 2
- to subtract, reverse the direction of vector 2 and add them together like normal
- can then use the Pythagorean Theorem and trig functions to find the length of the resultant vector and angle
5
Q
addition/subtraction of vectors that are not along the same direction and are not parallel
A
- use the component method - make a right triangle so you can use the Pythagorean theorem and trig functions to find the length of the resultant vector and the angle
6
Q
Pythagorean Theorem
A
- tells us the relationship between the length of the sides and the hypotonus of a right triangle
- a2 + b2 = c2
7
Q
Trigonometric functions
A
- the magnitude of angle θ is related to the different lengths of the sides of the triangle; for any right triangle with a specific angle, the ratio between its sides will always be the same; this can be used to determine the length of the sides
8
Q
sine
A
- ratio of the opposite to hypotenuse (SOH)
- sinθ = opp/hyp
9
Q
cosine
A
- ratio of adjacent to hypotenuse (CAH)
- cosθ = adj/hyp
10
Q
tangent
A
- ratio of the opposite to adjacent (TOA)
- tanθ = opp/adj
11
Q
Inverse trigonometric functions
A
- Used to find the angle when you just know the lengths of the sides
12
Q
inverse sine
A
- θ = sin-1 (opp/hyp)
13
Q
inverse cosine
A
- θ = cos-1 (adj/hyp)
14
Q
inverse tangent
A
- θ = tan-1 (opp/adj)
