أكاديميا - كولنز - معاجم الجيب العلمية - الفيزياء - الجدول 3 التعابير _٢_

Academia - Collins - Pocket Scientific Dictionaries - Physics - English - French - Arabic - Appendix - Table 3 Expressions _2_


Focal distance (unit: meter)
Focal distance(f)

(V is the image distance and u is the object distance)
1/f = 1/v + 1/u

(for a mirror) f = r /2

(And P is the power of the lens, mirror, or system)
f = 1/p


Force (unit: newton)
Force (F) (unit: N)

(Definition) F = ma

(to move an object) F= P/ν

(W is work or energy)
f = W/S

Power ratio (mechanical advantage)
Force ratio

Power ratio = load / effort


Focal number (unitless)
f-number (f/)

Focal number = focal distance / aperture diameter = f/

Frequency (unit: Hz)
Frequency(f)

(from the wave equation)
f = C / λ

(Definition) f = 1/t

(how much radiation) f = W/h


Gravity field force
(Unit: newton/kg or meter/s2).
Gravitational field strength(g)


(Definition: W is weight)
g = W/m

(For a pendulum) g = T2/ 4π²I
See also: acceleration.

Mass (unit: kg) Mass (m)

(Inertial mass) m = F/a

(For gravitational mass) m = w/g

(and D is the density) m=DV

Torque (unit: Newton/meter)
Moment(T)

(Definition) T = Fs

Momentum (unit: kg m/s) Momentum

(Definition) Momentum = mv

(From Newton's laws of force)
Momentum = Ft

Cycle (unit: sec) Period (T)

(Definition) T = 1/v

(For a pendulum) (1/8) Т = 2π


Planck's constant (unit: joule second)
Planck's constant (h)


(From quantum theory) h = w/f

Power (unit: diopter) Power (P)

(of a lens, mirror, or system) P = f/1

Power (Unit: Watt) Power (P)

(Definition) p = w/f

(For a moving body) p = Fv

(From the definition of voltage) p = VI

(For current) P = I2R

(For voltage) P = V2/R

Pressure (unit: pascal)
Pressure(p)

(Definition) P = F/A

(in a fluid) P = hDg

(ideal gas) P = kT/V


Radius of curvature (unit: meter)
Radius of curvature(r)

(for a mirror) r = 2f

Index of refraction (no unit)
Refractive index (n)

(definition)

Velocity in the medium1/velocity in the medium2 = n

(from the law of refraction)
n = sin i /sin r

(and C is the critical angle)
n = 1 / sin c
True depth/apparent depth = n

Relative density without unity)
Relative density

Relative density = density of matter / density of water Ds/Dw