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## Homework Statement

heres a problem i working on

a block slides on a horizontal surface which has been lubricated with a heavy oil such that the block experiences a viscous drag

resistance in the opposite direction to the velocity and that varies with speed according to:

[tex]F\left( v\right) =-c\,i\,{v}^{n}[/tex]

if the initial speed is [itex] v_0 [/itex] at [itex] t=0 [/itex]

a) find [itex]v[/itex] as a function of time [itex]t[/itex]

which iv found ;

[tex]{\left( {v_o}^{1-n}+\frac{c\left( n-1\right) \,t}{m}\right) }^{\frac{1}{1-n}}[/tex]

b) For [itex]n = \frac{1}{2} [/itex] find the displacement x[itex]\vec{i} [/itex] as a function of t: i is the unit vectoer in x direction. .

which iv found

[tex] x- x_o = \frac{12\,{m}^{2}\,t\,vo+6\,c\,m\,{t}^{2}\,\sqrt{vo}+{c}^{2}\,{t}^{3}}{12\,{m}^{2}}[/tex]

c) show that for [itex] n = 1/2 [/itex] , the block will not travel further than [tex] \frac{2mv_o^{\frac{3}{2}} }{3c} [/tex]

now this is the sucker that will not work out. the answers for a and b are as given in the

assignment sheet, so they are ok.

## Homework Equations

## The Attempt at a Solution

give me a clue on how to do this