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Flashcards in Equations Deck (34):
1

Big Five #2
(missing d)

v = v0 + at

2

Big Five #3
(Missing v)

d = v0t + 0.5at^2

3

Big Five #5
(missing t)

(v^2) = (v0^2) + 2ad

4

Newton's first law

If Fnet = 0, change in v = 0

An object in motion will stay in motion unless acted upon by an outside force

5

Newton's second law

F = ma

6

Newton's third law

For every action there is an equal and opposite reaction

I.e. The force exerted by A on B will be equal and opposite to the force exerted by B on A

7

Work (Newtonian)

W = Fdcosθ, units: J

Angle is between F and direction of motion

Work-energy theorem: Wtot = ΔKE

P = W/t, units: Watts

8

Thermodynamics

ΔE = Q - W

W = PΔV

V = free space in the vessel

W = area under curve on PV diagram

W and Q are path-dependent

9

Buoyant force (Archimedes' principle)

Fbuoy = (ρfluid)(Vsub)g = Wobj

Vsub/V = ρobj/ρfluid

10

Continuity equation

A1v1 = A2v2

The rate at which a fluid enters a system is equal to the rate at which the fluid exits the system

11

Electric field/force relation

Fe = qE (force exerted by a field on a point charge)

E = kQ/(r^2) (field due to a point charge); units = N/C or V/m

12

Electric potential energy/potential relation

ΔPE = qΔφ = qV

φ = kQ/r, units: C/m

Work done by field = -ΔPE

13

Ohm's Law

V = IR

14

Period/frequency relationship (waves)

f = 1/T

T = 1/f

Small angle approx for pendulum: not dependent on mass

15

Doppler effect

fd = fs(v + or - vd)/(v - or + vs)

If s and d are getting closer, use top signs

16

Snell's Law

n1sinθ1 = n2sinθ2

n = c/v

sin(θc) = n2/n1

17

Mirror/lens equations

(1/o) + (1/i) = (1/f)

m = (-i/o)

P = 1/f

18

Mirror/lens conventions

Concave mirror/convex lens: +f, can produce real or virtual images

Convex mirror/concave lens: -f, only produce virtual images

-i = virtual, upright
+i = real, inverted

19

Henderson-Hasselbach

pH = pKa + log([A-]/[HA])

20

Galvanic cell

Cathode: reduction
Anode: oxidation

Standard conc. is 1 M in each half cell

If both cells use the same element, E = 0

ΔG = -nFE

21

Impulse

J = FΔt = ΔP

P = mv

22

Springs

Fs = -kx

W = (kx^2)/2

23

Sound

dB = 10log(I/Io)

For every 10 dB increase, a sound is 10x more intense

I = P/A

24

Torque

T = rFsinθ

θ measured as if F and r originate at the same point, always <180

25

Gibbs' free energy

ΔG = ΔH - TΔS

Thermodynamic, not kinetic

+ΔG = nonspontaneous
-ΔG = spontaneous

Standard ΔG = -RTlnKeq

26

Circuit conventions

Series:
-R is summative
-C is inversely summative
-I is constant
-C is summative

Parallel:
-R is inversely summative
-C is summative
-I is summative
-V is constant

27

Friction

Ff = μFn

μk < μs

28

Uniform circular motion

Fc = ma = m(v^2/r)

29

BDE

E(separate atoms) - E (bonded)

= 0 - E

E(bonded) always - so BDE always +

Breaking a bond requires energy

30

Capacitance

C = κεA/d

PE = CV^2/2 = Q^2/2C

31

Types of decay

α: lose 4 mass units and 2 protons

β: lose an electron (atomic # increases)

Neutron capture: mass # increases

Electron capture: electron combines with proton, mass # same but atomic # decreases

γ: photon emission

32

Dalton's Law

Sum of partial pressures of gases in a mixture equals the total pressure of the mixture

Partial P = mole fraction x Ptot
Py = XyPtot

ppm = mole fraction x 1,000,000

33

Venturi effect

When fluid flows through a narrow section of the container, pressure drops

34

Boyle's Law

At constant temperature, pressure and volume for an ideal gas are inversely related