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  formulae of mechanics........plzzzz see.................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!   12 Nickels awarded!
Tagged with:    [Post New]posted on 23 Aug 2007 12:23:11 IST    
Formulas
 and
Symbols of mechanics........!!!!!!!!!!!!!

Physics I        
 Quantity Symbol Formula
% Error   % Error = ( |A-M| ) x 100 /A
% Uncertainty   % Uncertainty = (Uncertainty x 100) / Measurement
Distance (Linear displacement) Dx Dx = xf - xo
Elapsed Time Dt Dt = t2 - t1
Instantaneous Speed V V = Dd / Dt  
(with t approaching zero seconds)
Average Speed Vavg Vavg = (total distance traveled)/(total elapsed time)
Acceleration a a = DV/Dt  =   (V2 - V1) / (t2 - t1)
Final Speed V2 V2 = V1 + aDt
 Original Speed V1 V1 = V2 - aDt
Elapsed Time Dt Dt = (V2 -  V1) / a
Kinematic Equations: ====> (Uniform Acceleration)
Final Velocity V2 V2 = V1 + aDt
Displacement Dx Dx = V1Dt + 0.5(aDt2)
Final Velocity V2 V22  =   V12 +  2aDx
Displacement Dx Dx = 0.5(V2 + V1)Dt
Elapsed Time Dt Dt = (V2 -V1) / a



Free Fall from Rest V1 = 0.0 m/s g =  -9.8 m/s2
Final Velocity V2 V2 =  gDt
 Displacement   Dx Dx = 0.5(gDt2)
Final Velocity V2 V22  =  2gDx
Displacement Dx Dx = 0.5(V2 )Dt
Elapsed Time Dt Dt = (V2) / g
Elapsed Time Dt Dt = Sq. root of (2Dx/g)
     
 Dynamics  Equations  
Force (Newton's 2nd Law) F = Force F = ma
 Friction Ff Ff = mFn
Newton's Third Law . FAB = -FBA
Weight Fg = F Fg = Fw = mg
 Normal Force Fn Fn = FwCos q  
Coefficient of Friction m m= Ff / Fn
Atwood Machine    
Net Force Fnet Fnet  =  (M1- M2)g  =  DMg
Acceleration a a = (Fnet ) / (M1+ M2)
Net Force Fnet Fnet = (M1+ M2)a
Mass 1 M1 .
Mass 2 M2 .
Total Mass Mtot Mtot  = M1+ M2
Mass Difference DM DM = M1- M2



Force and
on an
Acceleration
 incline
  
Angle of Incline q q  =  Sin-1(Opp/adj)
Acceleration (net) a a = gsin q
Accelerating Force Fa Fa  =  Fw (Sin q)
Normal Force FN FN = Fw (Cos q)
Vertical Acceleration ay ay = gsinqsinq
Horizontal Acceleration ax ax = gsinqcosq
     
Projectile Motion

(No Air Resistance!) x = horizontal,
 y = vertical
(Acceleration is in the vertical direction only!)
ax = 0.0 m/s2,  ay = 9.8 m/s2 Down vectors are negative in Value! Subscript "o" means time is 0.0 seconds
    Up vectors are positive in value! Formulas require ay to be positive 9.8 m/s2.   (The negative value has already been entered into the formulas for acceleration!)
Horizontal Motion

x2 = x1 + Vx1t Vx2 = Vx1 ax = 0.0 m/s2
Vertical Motion      
y2 = y1 + Vy1t - 0.5gt2 Vy2 = Vy1 - gt V2y2  =  V2y1 - 2gDy
         
Projectile Terms and Units:      
x2 Final Horizontal Position (meters) Dx = x2 - x1 =   Vx1t
x1 Initial Horizontal Position (meters) x1 = x2 - Vx1t
Vx1 Initial Horizontal Velocity (m/s) Vx1 = (x2 - x1) / t  = Vx2
Vx2 Final Horizontal Velocity (m/s) Vx2  = Vx1  =  (x2- x1) / t
ax   Horizontal Acceleration (m/s2) ax = 0.0 m/s2
y2 Final Vertical Position 
(m)
Dy = y2 - y1  Vy1t - 0.5ayt2
 y1 Initial Vertical Position 
(m)
y1 y2 - Vy1t + 0.5ayt2
Vy1 Initial Vertical Velocity (m/s) Vy1 = Vy2 + ayt
Vy2  Final Vertical Velocity (m/s)  Vy2 = Vy1 - ayt
Dy Change in Vertical Position (m) Dy = (y2  - y1)
ay Earth's Gravitational Acceleration (m/s2)  ay = g = -9.8 m/s2
t Time of "flight" (s) t = (Vy2  - Vy1) / ay
Projectile Launched
 at angle q
 from the horizontal
q Angle of Launch from the horizontal (degrees) q =  tan -1 (Vy1 / Vx1)
V1 Resultant Launch Velocity V21  V2y1V2x1
Vx2 Horizontal Launch Velocity (Component) Vx2  = V1 . Cos q
Vy1 Vertical Launch
Velocity (Component)
Vy1  = V1 . Sin q
R  (if,  y2 = y1) Maximum Horizontal Distance traveled
(or Range)  in meters
R = (V21 Sin 2q) / g
Momentum
(Linear)  Units:            P = kg.m/s     J = N.s
P Momentum P = mV
J Impulse J = F.t
DP Change in Momentum D(mV)  =  m(Vf - Vo)
J = DP Impulse = Change in Momentum F.t  = D(mV)
Ptot = SmnVn Total Initial Momentum m1V1 + m2V2 + m3V3 + .....
P'tot =SmnV'n Total Final Momentum m1V'1 + m2V'2 + m3V'3 + .....
Ptot =P'tot Conservation of Momentum m1V1 + m2V2 + m3V3 + ..... = m1V'1 + m2V'2 + m3V'3 + .....
Explosions and Collisions:
Type: Momentum Formulas
   Elastic Collision m1V1 + m2V2 = m1V'1 + m2V'2
   Inelastic Collision m1V1 + m2V2 = (m1 + m2)V'f
   Explosion 0 = m1V'1 + m2V'2 + m3V'3 + .....
Work and Energy
(Linear Mechanical System)  
Work W W = F.d Cos q
Gravitational Potential Energy Ep Ep = Fw(h) = mgh
Kinetic Energy Ek Ek = (0.5)mv2
Work W W = DEk + DEp
Work W W = DEk + DEp = (0.5mv2 + mgh)f - (0.5mv2 + mgh)
Total Energy (system) SE SE  =  Ek + Ep + heat
Conservation of Energy Initial Total Energy = (SE)i (SE)i = (SE)f
Conservation of Energy Final Total Energy = (SE)f
 or        (Ek + Ep + heat)i  = (Ek + Ep + heat)f









About the Author:
nivedh_89 (4573)

Blazing goIITian

Olaaa!! Perrrfect answer. 835  bad job dude!! I dont approve of this answer! 1  [1036 rates]

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ac
ac is offline comment by ac    (posted on 23 Aug 2007 12:57:58 IST)
This list comes in handy for revision, will help people. Your articles are adding value to this community. Try and put in some of the conclusions/notes you have made about topics during the course of your study. These are generally not found in any book, and help a lot. Keep writing!!

AC (IIT Delhi alumnus, forum expert)
nivedh_89
nivedh_89 is offline comment by nivedh_89    (posted on 23 Aug 2007 13:40:52 IST)
thank u SIR...............................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
cutepooja is offline comment by cutepooja    (posted on 23 Aug 2007 14:31:36 IST)
gr8
swashata4iit
swashata4iit is offline comment by swashata4iit    (posted on 23 Aug 2007 14:39:38 IST)
This is really nice. keep it up. But do remember dat it is time consuming
kamalasai
kamalasai is offline comment by kamalasai    (posted on 23 Aug 2007 15:44:27 IST)
its good.........
nivedh_89
nivedh_89 is offline comment by nivedh_89    (posted on 23 Aug 2007 17:14:58 IST)
thanx.............................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
rini
rini is offline comment by rini    (posted on 23 Aug 2007 17:27:20 IST)
gud..
rasheed786 is offline comment by rasheed786    (posted on 23 Aug 2007 18:12:28 IST)
sir can u plz post such imp formulas for other topics?
specially of 12
nivedh_89
nivedh_89 is offline comment by nivedh_89    (posted on 23 Aug 2007 18:15:00 IST)
like for wch topics.............................................?????????
i hav already posted some for integration,conics,etc..................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
apurviitjee2008
apurviitjee2008 is offline comment by apurviitjee2008    (posted on 23 Aug 2007 18:52:40 IST)
very good concise formula sheet
dream_iit
dream_iit is offline comment by dream_iit    (posted on 23 Aug 2007 20:59:09 IST)
hey , can u post shortcuts , these we can find in some books , but u collected all here , so thank u , but can u post some shortcuts....it will b a lot help...
and yes , how many formulas can we learn , so its also a burden coz syllabus is also not less , vo toh finish hota nahi hai....
so if u post some shrtcts i will b helpful
nivedh_89
nivedh_89 is offline comment by nivedh_89    (posted on 25 Aug 2007 14:47:22 IST)
i will try.......................!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
nivedh_89
nivedh_89 is offline comment by nivedh_89    (posted on 27 Aug 2007 12:20:51 IST)
neways thanx for the rates.........!!!!!!!
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