QUICK REVISION FORMULAS

 

 

🎯1. Formulas related to force:

🗯️F = ma

🗯️F = kx

🗯️F = m(vf² - vi²/2S)

🗯️F = mv/t

🗯️F = md/t²

🗯️F = m(vf - vi)/t

🗯️F = Area × density × velocity²

🗯️F = 1/2 mv²/d

🗯️F = 1/2 Pv/d

🗯️F = Power/velocity

🗯️Fc = mv²/r

🗯️Fc = mrw²

🗯️Fc/2 = mv²/2r

🗯️Fc = 2K.E/r

🗯️F = Area × Stress

🗯️F = pir² × stress

🗯️F = YA × Strain

🗯️F = YAl/L

🗯️F = pressure × area

🗯️F = change in momentum × time interval

🗯️F = - 2mVx × Vx/2l

🗯️F2 = F1/A1 × A2

🗯️F = qE

🗯️F = kQ/r²

🗯️F = ILB sintheta

🗯️F = q (v × B) 

🗯️F = qE + q(v × B)

🎯2. Formulas related to energy and work

👉Fd = k.e

👉mgh = 1/2 mv²

👉E = 1/2 kx²

👉E = Ve

👉E = nhf

👉E = nhc/lambda

👉E = Pc

👉K.e = hf - work function = hf - hf° = hf - hc/w° (here w° is cutt off wavelength) 

👉E = 1/2 Pv

👉mv²/2r= Fc/2

👉K.E/r = Fc/2

👉K.E = Fc×/r/2

👉K.e = 1.5 KT

👉E = VQ

👉E = Power × time

👉E = Fvt

👉% loss in K.e = v1² - v2²/v1² × 100

👉% loss in P.e = h1² - h²/h1² × 100

👉Energy lost due to air friction(Fh) = 1/2mv² - mgh (when body is thrown upward) 

👉Energy lost due to air friction(FS) = mgh - 1/2mv² (when body is thrown downward) 

👉E = 1/2 CV² (capacitor) 

👉E = R × hc (R is Rydberg' constant) 

J = m-¹ × Js ms-¹

👉hf kalpha x rays = EL - Ek

hf kbeta x rays = EM - Ek

👉Binding energy = mass defect × c²

👉W = Fd Costheta

👉W = nmgh (when person is climbing stairs) 

👉W = n(m+m) gh (when person is climbing stairs with some load)

👉W = 0mgh + 1mgh + 2mgh + 3mgh ....... (in case of stacking bricks. For ist brick h=0. For 2nd brick h=1. For 3rd brick h=2 and so on)

👉W = Fd = PA × change in V

👉W = Q - change in U

👉Q = mc × change in T

T/273.16 = Q/Q3 (Thermodynamic scale) 

👉W = I²Rt

👉W = emf×charge

👉W = VQ

👉W = 1/2 lF

👉W = YAl²/2L

👉W = StressAl²/2Strain 

👉W = PressureAl²/2Strain

👉W = Fl²/2Strain

🎯3. Formulas related to Power

💥P = Fv

💥P = E/t

💥P = n(mgh/t) 

💥P = Fd/t

💥P = mv²/2t

🎯4. Formulas related to distance, displacement, velocity and accelration

📝d = vt

📝d = at²

📝d = (vf + vi/2) ×t

📝d = 5t² (for distance in 'n' seconds) 

📝d = 5(2tn - 1) (for distance in 'nth' second) 

📝d = 1/2 mv²/F

📝d = vit + 5t²

📝d = v × underroot 2H/g

📝d = vt = x°wt = x°2pi/T × t = x°2pift

📝x = x° Sin wt

📝x = x° Sin (underroot k/m) t

vf = vi + at

📝2as = vf² - vi²

📝2as = (vi + at)² - vi²

📝2as = vf² - (vf - at) ²

📝v = underroot Vfx² + Vfy² 

📝v = Power/Force

📝v = 2×K.E/momentum (k.e = 1/2 Pv) 

📝v² = 2×Power×time/mass (P = mv²/2t)

v = underroot 2as

v = underroot gr (speed at highest point in a verticle circle)

v = underroot 5gr (speed at lowest point in a verticle circle) 

📝v² = 2FS/m

📝v² = 2E/m

📝v² = 2Ve/m

📝v = eBr/m (velocity of particle under action of magnetic force along circular path) 

📝v² = Force/Area.Density

📝v = w underroot x°² - x²

📝v = underroot k/m × underroot x°² - x²

📝v = x°w (at mean position where x=0)

📝v = x° underoot k/m

📝v = v° underroot 1 - x²/x°² (for determining ratio b/w inst. Velocity and maxi. Velocity) 

📝v= x°2pif = x°2pi/T

📝a = x°w² = x°w.w = vw = v.2pif

Common velocity = m1v1/m1+m2

📝vi² = Rg/Sin2theta

📝v = underoot Tension×length/mass

📝V = 2pi ke²/nh (speed of e- in nth orbit) 

📝Vn = V/n

📝v = nh/2pimr (lambda = 2pir and lambda=h/p) 

📝ma = kx

📝a = kx/m (SHM) 

📝a = - gx/l (Simple pendulum) 

📝ac = v²/r

🎯5. Formulas related to wavelength 'w' 

💭w = v/f

💭w = 1/wave number

💭w1 = 2l (when pipe is opened at both ends) 

💭w1 = 4l (when pipe is opened at one end) 

💭Delta w = Us/f (doppler shift) 

Wavelength for obs. = w - delta w = v/f - Us/f 

💭w = hc/Ve

💭w = hc/E

💭w = h/mv

💭w = h/P as P = underroot 2mE so

💭w = h/underroot 2mE (de Broglie wavelength) 

💭w = underroot 150/V A° (short method for de Broglie wavelength. This formula is applicable only for e-) 

💭1/w = RH (1/p²-1/n²)

💭Wmaxi/Wmini = n²/n²-p² (for determining ratio b/w maxi. Wavelength to mini. Wavelength for series of atomic spectrum) 

💭w = 2pir/n (n is no. of loops in a circle)

💭h/mv = 2pir