Physics - Ch 1: Kinematics and Dynamics

Question 1

SI units

Answer 1

Related to metric system

Question 2

Vectors

Answer 2

Physical quantities with magnitude and direction

Question 3

Scalar

Answer 3

Quantities without direction

Question 4

Vector addition

Answer 4

Tip to tip method or break up into components

Question 5

Vector subtraction

Answer 5

Change direction of subtracted vector and then add

Question 6

Vector x scale multiplication

Answer 6

Changes magnitude and could change direction

Question 7

Dot product

Answer 7

Results in scalar - product of magnitudes*cos(angle btwn them)

Question 8

Cross product

Answer 8

Results in vector - products of magnitudes*sin(angle btwn them) * u – use RHR to determine direction

Question 9

Displacement

Answer 9

Vector representation of a change in positions, path independent, equivalent to straight line distance between start and stop location

Question 10

Distance

Answer 10

Scalar quantity that reflects path travelled

Question 11

Velocity

Answer 11

Vector Representation of the change in displacement with respect to time (SI - m/s)

Question 12

Average velocity

Answer 12

Total displacement/total time

Question 13

Average speed

Answer 13

Total distance traveled/total time

Question 14

Instantaneous velocity

Answer 14

Limit of the change in displacement over time as the change in time approaches zero

Question 15

Instantaneous speed

Answer 15

Magnitude of the instantaneous velocity vector

Question 16

Force

Answer 16

Any push or pull that has the potential to result in an acceleration (SI - N=kg*m/s^2)

Question 17

Gravity

Answer 17

Attractive force between two objects as a result of their masses

Question 18

Friction

Answer 18

Force that opposes motion as a function of electrostatic interactions at the surfaces of two objects

Question 19

Static friction

Answer 19

Friction that exists between two objects that are not in motion relative to each other - can take on many values depending on the magnitude of force applied

Question 20

Kinetic friction

Answer 20

Friction that exists between two objects that are in motion relative to each other - constant value

Question 21

Coefficient of friction

Answer 21

Coefficient that depends on two materials in contact. Coeff of static friction is always higher than the coeff of kinetic friction - unitless

Question 22

Mass = weight?

Answer 22

NO

Question 23

Mass

Answer 23

Measure of the inertia of an object - its amount of material, scalar (SI - kg)

Question 24

Weight

Answer 24

The force experienced by a given mass due to its gravitational attraction to the Earth, vector (SI- N)

Question 25

Acceleration

Answer 25

Vector representation of the change in velocity over time (SI- m/s^2)

Question 26

Newtons first law

Answer 26

aka Law of inertia - an object with remain at rest or move with a constant velocity if there is no net force on the object

Question 27

Newton's Second Law

Answer 27

Any acceleration is the result of the sum of the forces acting on the object and its mass

Question 28

Newton's Third Law

Answer 28

Any two objects interacting with one another experience equal and opposite forces as a result of their interaction

Question 29

Linear motion

Answer 29

Motion in which the velocity and acceleration vectors are parallel or antiparallel

Question 30

Projective motion

Answer 30

Contains both an x and y components. assuming negligible air resistance, the only force acting on the object is gravity

Question 31

Inclined planes

Answer 31

Type of two-dimensional movement, easiest to analyze dimensions being parallel and perpendicular to surface of the plate

Question 32

Circular motion

Answer 32

Movement in circular direction, has radial and tangential dimensions

Question 33

Uniform circular motion

Answer 33

The only force is the centripetal force pointing radially inwards, the instantaneous velocity vector always points tangentially

Question 34

Free body diagrams

Answer 34

Representations of the forces acting on an object, useful for equilibrium and dynamic problems

Question 35

Translational equilibrium

Answer 35

Occurs in the absence of any net forces acting on an object, object has constant velocity, and may or may not also be in rotational equilibrium

Question 36

Rotational equilibrium

Answer 36

Occurs in the absence of any net torques acting on an object, constant angular velocity

Question 37

Torque equation

Answer 37

tau = r x F = rFsin(theta)*u

Question 38

Centripetal force

Answer 38

Force that points radially inward during circular motion, generates centripetal acceleration

Question 39

Vector magnitude

Answer 39

Use pythagorean theorem

Question 40

Magnitude of the gravitational force between two objects

Answer 40

F_g = (G*m1*m2)/r^2

Question 41

Static friction magnitudes

Answer 41

0<= f_s <= mu_s*N

Question 42

Normal force

Answer 42

Component of the force between two objects in contact that is perpendicular to the plane of contact between the object and the surface upon which it rests

Question 43

Kinetic friction magnitude

Answer 43

f_k = mu_k*N

Question 44

Relationship between weight and mass

Answer 44

F_g = m*g

Question 45

Center of mass/gravity

Answer 45

Where the weight of an object can be though of as being applied at a single point

Question 46

G (universal gravitational constant)

Answer 46

6.67E-11 N*m^2/kg^2

Question 47

Center of mass of a uniform object

Answer 47

Geometric center

Question 48

Deceleration

Answer 48

Acceleration in the direction opposite the initial velicty

Question 49

Average acceleration

Answer 49

Total change is velocity/total change in time

Question 50

Instantaneous acceleration

Answer 50

Average acceleration as DELTAT approaches 0

Question 51

Newtons second law equation

Answer 51

F_net = m*a

Question 52

Newtons first law equation

Answer 52

F_net = 0 if a=0

Question 53

Newtons third law equation

Answer 53

F_AB = -F_BA

Question 54

Kinematic equation v =

Answer 54

v = v_o + at

Question 55

Kinematic equation x =

Answer 55

x = v_o*t + a*t^2/2

Question 56

Kinematic equation v^2 =

Answer 56

v^2 = v_o^2 + 2*a*x

Question 57

Kinematic equation x =

Answer 57

v_bar*t

Question 58

Air resistance

Answer 58

Opposes motion of an object, its value increases as the speed of an object increases

Question 59

Drag force

Answer 59

Force opposing motion of an object, its value increases as the speed of an object increases until the drag force equals F_g

Question 60

Terminal velocity

Answer 60

Constant velocity where a falling objects force due to gravity equals the drag force

Question 61

Splitting gravity on inclined plane

Answer 61

``` F_gll = mgsin(theta) F_gperp = mgcos(theta) ```

Question 62

Centripetal force equation

Answer 62

F_c = m*v^2/r

Question 63

Dynamics

Answer 63

The study of forces and torques

Question 64

Rotational motion

Answer 64

Forces are applied against an object in such a way as to cause the object to rotate around a fulcrum

Question 65

Fulcrum

Answer 65

Fixed pivot point for rotational motion

Question 66

Torque

Answer 66

aka moment of force, application of a force a distance away from a fulcrum

Question 67

Positive torque direction

Answer 67

Counterclockwise