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Mechanics

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25 Mar 2007 11:38:04 IST

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10302

formulas!!!!!!!!!!!!

None

here are some shortcuts to find ............... in motion in 1 dimension

1) to find the vel. in b/w the distance travelled

V₁= {v² + (v²- u²/n)}^1/2

2) a bullet is fired with certain vel. into a block of wood . it loses 1/nth of its initial speed after travelling a dist. x in the block . determine the total dist. penetrated by it before coming to rest....

ans)

x' = {N²/ 2n - 1} x

where N is the amt of speed it loses (eg. if 1/10 th loses then N = 10)

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vikas p

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25 Mar 2007 11:45:20 IST

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thanx for making it luk easy

Himanshu

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25 Mar 2007 11:53:24 IST

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a vehicle of mass m travelling with vel. "v" stopped by applying const. braking force "f" within a dist. "x"

x/x * 100 = {(v₂)² - (v₁)²} / (v1)² * 100

% dec in v1 = 20%

then % dec in x = 30%

if dec in v1 = 10%

then dec in x = 19%

if inc. in v1 = 10%

inc. in x = 21%..............................

Himanshu

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25 Mar 2007 12:36:34 IST

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vel of projectile at any instant

v = { u² cos²

+ ( u sin

-gt)²}^1/2

Himanshu

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25 Mar 2007 12:39:28 IST

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least counts............

meter scle = 10^-3 m

vernier caliper = 10^-4m

screw gauge = 10^-5m

wall clock = i sec.

stop clock = 1/100 sec.

spherometer = 1/100 mm

Himanshu

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25 Mar 2007 13:12:09 IST

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hope these are benificial

i will b posting more here in the evening or tomm.......

Himanshu

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25 Mar 2007 14:27:47 IST

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... vel. = 3v1v2v3 /v2v3 + v3v1 + v1v2

... a machine is delivering const. power
then ,

x (displacement)

t^3/2{x= (8p/9m)^1/2. t^3/2}

v (velocity)

t^1/2{v= (2p/m)^1/2.t^1/2}

Himanshu

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25 Mar 2007 14:49:51 IST

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here's another

A person throws a ball with vel. v at an angle

to the horizontal. another person starts running along the plane of projectile motion in hor. direction such that ball always remain over his head. the vel. of he person is..............

v = u cos

Himanshu

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25 Mar 2007 15:29:01 IST

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wen distance is same.....................

V_avg.= 2v₁v₂/v₁+ v₂

in three..........

V_avg = 3v₁v₂v₃/ v₂v₃+v₁v₃+v₁v₂

wen time is same ,

V_avg = v₁+ v₂+ v₃ +.........................+v_n/n

Himanshu

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25 Mar 2007 15:32:44 IST

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in projectiles...............

y = xtan$ {1 - x/R}

R = range............

diksha jeena

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25 Mar 2007 16:24:25 IST

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great work

good going!!!!!

Himanshu

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25 Mar 2007 17:23:42 IST

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thanx.........

vishak p

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25 Mar 2007 17:43:29 IST

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gud yaar ! i wanted some of these thanks for ur efforts ~

Revathi _pearl

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25 Mar 2007 19:07:43 IST

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thanx........a lot .........plz keep posting gud heplful info...like this...

Himanshu

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25 Mar 2007 19:43:46 IST

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for a projectile motion...............

R / H = 4 /tan $

Himanshu

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25 Mar 2007 21:25:02 IST

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hey plz if neone know any shortcut in mechanics plz post it

Himanshu

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26 Mar 2007 10:38:20 IST

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for angle $ and pi - $ range is same u all know
but

T1 (for $) + T2 (for pi - $ ) = 2R/g

H1 (for $) + H2(for pi - $ ) = Hmax.

H1 . H2 = R^2/16

Himanshu

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26 Mar 2007 11:14:10 IST

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min. no. of equal vectorsthat can give zero resultant is 2
" " " un= " " " " " " " 3

and in case of unequal vectors all the three vectors must form a triangle

Himanshu

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26 Mar 2007 11:26:19 IST

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two vectors give resultant = to either of them wen angle b/w them is 120 degress

mag. of vector addition = mag. of vector subtraction wen angle b/w them is 90 degrees

mag of dot product = mag. of cross product wen angle is 45 degress

Himanshu

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26 Mar 2007 13:01:51 IST

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in projectiles
hor. component of vel. always remain the same

projectile is at sum ht fr 2 timings sum of wich is time of flight (plz say if u don't understand this one)

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