Chapter 1: Units and Kinematics

Question 1

Fundamental units of SI system; length, mass, force, time, work/energy, and power

Answer 1

Length: meter (m)
Mass: kilogram (kg)
Force: Newton (N)
TIme: second (s)
Work/Energy: joule (J)
Power: watt (W)

Question 2

Multiples and submultipes

Answer 2

Multiples
-- giga (G) 10^9
-- mega (M) 10^6
-- kilo (k) 10^3
Submultiples
-- centi (c) 10^-2
-- milli (m) 10^-3
-- micro (µ) 10^-6
-- nano (n) 10^-9
-- pico (p) 10^-12

Question 3

Scientific notation: multiplication

Answer 3

multiply significands and add exponents

Question 4

Scientific notation: division

Answer 4

divide significand in numerator by significand in denominator, then subtract exponent from denominator from exponent from numerator

Question 5

Scientific notation: raising to a power

Answer 5

significand raised to the poser and exponent multiplied by that power

Question 6

Scientific notation: addition and subtraction

Answer 6

must have same exponents; add/subtract significands and then use same exponent

Question 7

Trigonometric relations: sin function of important angles

Answer 7

angle = sin(angle)
0 = 0
30 = 0.5
45 = sqrt2/2 =~0.707
60 = sqrt3/2 =~0.866
90 = 1
180 = 0

Question 8

Trigonometric relations: cos function of important angles

Answer 8

angle = cos(angle)
0 = 1
30 = sqrt3/2 =~0.866
45 = sqrt2/2 =~0.707
60 = 0.5
90 = 0
180 = -1

Question 9

Logarithms (definition)

Answer 9

the logarithm of a number to a given base is simply the power to which that base must be raised to equal that number
log(base10)x=y => 10^y = x

Question 10

Rules of logarithms

Answer 10

log(mn) = log m + log n
log(m/n) = log m - log n
log(m^n) = n log m

Question 11

Vectors vs scalars

Answer 11

Vectors = magnitude and direction
Scalars = magnitude, no direction

Question 12

Vector addition

Answer 12

(1) head to tail method: place the head of one vector next to the tail of the other vector and the resultant vector is from the tail of the first to the head of the second
(2) resolve the vectors into their components, add each component separately, use pythagorean theorem to determine the magnitude of the resultant vector and use trigonometric functions to determine the direction of the resultant function

Question 13

Vector subtraction

Answer 13

A - B = A + (-B)

Question 14

Multiplying a vector by a scalar

Answer 14

multiplying a vector by a scalar changes either the length, the direction, or both the length and the direction

Question 15

Kinematics (definition)

Answer 15

branch of Newtonian mechanics that deals with the description of motion

Question 16

Displacement

Answer 16

Change in an object’s position in space, vector quantity; does not account for the actual pathway

Question 17

Velocity

Answer 17

rate of change of displacement in a given unit of time; vector w/ units meter/second

Question 18

Speed

Answer 18

rate of change of distance in a given unit of time; scalar with units meter/second

Question 19

Instantaneous speed and instantaneous velocity

Answer 19

Instantaneous speed: always the magnitude of an object’s instantaneous velocity
Instantaneous velocity: measure of the average velocity as the change in time approaches 0

Question 20

Average speed and average velocity

Answer 20

Average speed accounts for actual distance traveled whereas average velocity does not
v(avg) = ∆x/∆t

Question 21

Acceleration

Answer 21

rate of change of velocity over time; vector quantity w/ units m/s^2

Question 22

Average acceleration

Answer 22

change in instantaneous velocity over the change in time; a(avg) = ∆v/∆t

Question 23

Instantaneous acceleration

Answer 23

average acceleration as ∆t approaches zero

Question 24

Motion with constant acceleration: Linear motion and equations

Answer 24

• motion with constant acceleration
• object’s velocity and acceleration are along the line of motion; pathway of moving object is a straight line
• equations
  (1) v = v0 + at
  (2) x - x0 = v0t +(1/2)at^2
  (3) v^2 = v0^2 + 2a(x-x0)
  (4) v(avg) = (1/2)(v0+v)
  (5) ∆x = v(avg)t = (1/2)(v0+v)t
• -note regarding the equations: v0 and x0 are v and x at t=0; when the motion is vertical, use y instead of x; in using the equations, remember that velocity and acceleration are vector quantities

Question 25

Free fall

Answer 25

type of linear motion where the object’s weight is the only force acting upon it; falls with constant acceleration

Question 26

Motion with constant acceleration: Projectile motion

Answer 26

• motion that follows a path along two dimensions
• analyze v & a separately for each component
• only y-component will experience force of gravity, so v(y) changes at the rate of g, but v(x) is constant (there is no horizontal acceleration)