A stone sliding over a horizontal ice surface stops after moving a distance S=48m.
Determine the initial velocity of the stone 'u' if the force of sliding friction of the stone against the ice is 0.06 of the weight of the stone.

Question

A stone sliding over a horizontal ice surface stops after moving a distance S=48m.
Determine the initial velocity of the stone 'u' if the force of sliding friction of the stone against the ice is 0.06 of the weight of the stone.

maheshmeghwal9 · Answer

@FoolAroundMath @Australopithecus Please help:)

maheshmeghwal9 · Answer

Its answer is given
u = 7.56 m/s
but I don't know how to get it???????

maheshmeghwal9 · Answer

@Vaidehi09 :)

foolaroundmath · Answer

Can you find the frictional force and correspondingly the acceleration of the block ?

Then use $v^{2} - u^{2} = 2as $ to find $u$

anonymous · Answer

u have v = 0, s = 48m
and F = 0.06mg....this force offers the deceleration.
so 0.06mg = -ma
a = -0.06g
sub in v^2 = u^2 + 2as.

maheshmeghwal9 · Answer

how did u gt
0.06mg=-ma ??????

anonymous · Answer

the only force acting in the line of motion is the friction.

maheshmeghwal9 · Answer

isn't there$$mg \sin \theta$$also acting????????????

anonymous · Answer

why? its a horizontal surface...not an inclined one.

maheshmeghwal9 · Answer

would u plz make the figure for me?

foolaroundmath · Answer

frictional force = 0.06*weight = 0.06mg

This provides the deceration. So, 0.06mg = -ma

and why $mg\sin{\theta}$? Its a horizontal surface

anonymous · Answer

work done by friction is equal to cange is kinetic energy....
as final velocity is 0....

and friction is 0.06mg


$$\frac{1}{2}mv^{2}=0.06mg(s)$$

anonymous · Answer

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