Formulas And Constants Conglomerate 1

Front 1

What is frequency (in terms of period)?

Back 1

f = 1/T (Unit: Hertz, Hz, cycles per second)

Front 2

What is period (in terms of frequency)?

Back 2

T = 1/f (Unit: seconds, s)

Front 3

What is the speed of any wave?

Back 3

v = λ/T or v=λf (v is speed, λ is wavelength, T is period, f is frequency) (Unit: meters per second, m/s)

Front 4

What is the speed of sound (formulaically)?

Back 4

Vsound = 331.4 + 0.6Tc (Tc is temperature in celsius) (Unit: meters per second, m/s)

Front 5

What is the speed of sound at STP?

Back 5

331.4m/s

Front 6

What is the speed of sound at room temperature?

Back 6

343.2m/s (around 340m/s)

Front 7

What is the speed of light in a vacuum (or, with a negligible difference, air)?

Back 7

Vlight = 3 * 10^8 m/s

Front 8

What is the mathematical formula for a wave?

Back 8

y=Acos[kx-wt] or y=Asin[kx-wt] (Unit: cosine and sine are unitless, so the unit is the same as the amplitude, usually meters)

Front 9

What is the wave number? (k in the mathematical formula for a wave)

Back 9

k=2π/λ (Unit: 1/m or m^-1)

Front 10

What is the angular frequency? (w in the mathematical formula for a wave)

Back 10

w=2π/T or w=2πf (Unit: 1/s or s^-1)

Front 11

What is the wavelength of blue light?

Back 11

450nm (400nm is close enough)

Front 12

What is the wavelength of red light?

Back 12

700nm

Front 13

What is the energy of a single photon?

Back 13

E=hf or E=hc/λ (Unit: Joules, J)

Front 14

What is intensity?

Back 14

I=P/A or I=P/4πr^2 (I is intensity, P is power, A is area, r is radius) (Unit: Watts per meter squared, W/m^2)

Front 15

What is intensity level?

Back 15

β=10Log(I/Io) (β is intensity level, I is intensity, Io is reference intensity, threshold of hearing) (Unit: NONE! Decibels can be used, dB)

Front 16

What is the reference intensity (threshold of hearing)?

Back 16

Io = 10^-12 W/m^2

Front 17

What is change in intensity level?

Back 17

Δβ=|10Log(I2/I1)| (Δβ is change in intensity level, I2 is intensity 2, I1 is intensity 1) (Unit: NONE! Decibels can be used, dB)

Front 18

What is the speed of a wave on a string?

Back 18

v=sqrt(Ft/μ) (v is speed, Ft is tension, μ is mass density of the string) (Unit: m/s)

Front 19

What is the mass-density of a string?

Back 19

μ=M/T (μ is mass density, M is total mass of the string, L is total length of the string)

Front 20

What is the beat frequency?

Back 20

fbeat = |f2-f1| (Unit: Hertz, Hz)

Front 21

What is the mass of a proton?

Back 21

1.672*10^-27 kg

Front 22

What is the mass of a electron?

Back 22

9.11*10^-31 kg

Front 23

What is the mass of a neutron?

Back 23

1.672*10^-27 kg + 9.11*10^-31 kg (around the same as a proton)

Front 24

What is the charge of a proton?

Back 24

1.6 * 10^-19 C (+)

Front 25

What is the change of an electron?

Back 25

1.6 * 10^-19 C (-)

Front 26

What is the charge of a neutron?

Back 26

0C

Front 27

What is the fundamental charge?

Back 27

1.6 * 10^-19 C

Front 28

What is total charge?

Back 28

qtotal = n*qe (qtotal is total charge, n is the number of charges, always an integer, qe is the fundamental charge) (Unit: Coulombs, C)

Front 29

What is the electrostatic force?

Back 29

Fe = kq1q2/r^2 (Fe is iron or electrostatic force, your choice. k is electrostatic constant, q1 and q2 are the charges this force is between, r is radius between the two charges) (Unit: Newtons, N)

Front 30

What is the electrostatic constant?

Back 30

k = 9 * 10^9 N*m^2/C^2

Front 31

What is the gravitational force?

Back 31

Fg = Gm1m2/r^2 (Fg is gravitational force, G is gravitational constant, m1 and m2 are masses this is in between, r is radius) (Unit: Newtons, N)

Front 32

What is the gravitational constant?

Back 32

G = 6.67*10^-11 N*m^2/kg^2

Front 33

What is the magnitude of the resultant vector of the x and y components Ax and Ay?

Back 33

Anet = sqrt(Ax^2 + Ay^2)

Front 34

What is the direction of the resultant vector of the x and y components Ax and Ay?

Back 34

φ = tan^-1[Ay/Ax]

Front 35

What is the formula for electric field due to charge q at point p?

Back 35

Ep = F/|qo| or Ep = kq/r^2 (Ep is electric field at point p, F is electrostatic force, qo is a positive test charge, k is the electrostatic constant, q is the charge producing the electric field, r is radius between charge and the point) (Unit: Newtons per coulombs, N/C)

Front 36

What is electric potential?

Back 36

V=kq/r or V=Ed (V is electric potential [or voltage, kind of], k is electrostatic constant, q is charge, r is radius, E is electric field, d is distance) (Unit: Volts, V)

Front 37

What is electrostatic potential energy (work done moving a charge from point i to f)

Back 37

Wi->f = qo * ΔV (Wi->f is work done moving a charge from point i to f, or electrostatic potential energy. qo is the moving charge, ΔV is change in electric potential, ΔV = Vf - Vi) (Unit: Joules, J)

Front 38

What is the capacitance in terms of area and distance?

Back 38

C = EoA/d (C is capacitance of a parallel-plate capacitor, Eo is the electric constant, A is area of the plates, d is distance the plates are separated) (Unit: Farads, F)

Front 39

What is the electric constant? (Eo)

Back 39

Eo = 8.85 * 10^-12 F * m^-1

Front 40

What is capacitance in terms of charge and voltage?

Back 40

C = Q/V (C is capacitance, Q is magnitude of charge on either plates, V is magnitude of voltage difference between the plates) (Unit: Farads, F, Coulombs per volt, C/V)