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akumar_ak

a car is driven by a constant power.if the car moves over a distance x, then velocity v attained by the car will be related to x as
a) v directly proportional to x^1/3
b) v dire.......................... to x^1/2
c) v direct........................ to x^-1/3
d) v directly..................... to x^-1/2
plz reply with proof...

please say sumthing
i got only 15mins more
chimanshu,don,ckmr?
where are u all?

TRANSLTR

are the options correct?

akumar_ak

damn it...i dunno

TRANSLTR

elessar_iitkgp

Given
P = k (a constant)
Fv = k
m(dv/dt)v = k
m(dv/dx)(dx/dt)v = k
mv²(dv/dx) = k
m₀

^v v²dv = k₀

^x dx
mv³/3 = kx
v = (3kx/m)^1/3
v

x^1/3

jaysunantony

constant power means.........

F*v is constant............

so a.v is constant.........

now, v²= 2.a.x.............as it definitely start from rest.........

so a= v²/2x

now............v²/2x . v is constant..............or v³= const .2x

v prop. to x^1/3

hope I made it Simmmmmmmmm........mm.........pp........le................

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