Determine an expression for the velocity va of the cart a down the incline in terms of the upward velocity vb of cylinder


b. If h = 1.57 m, x = 3.17 m, and vb = 3.03 m/s, what is va?

Respuesta :

Given :

h= 1.57 m, x = 3.17 m, and vb = 3.03 m/s .

To Find :

The upward velocity [tex]v_b[/tex] of cylinder .

Solution :

Component of [tex]v_a[/tex] along string [tex]v_s= v_acos\ \theta[/tex] .

Now ,

[tex]tan\ \theta=\dfrac{h}{x}\\\\cos\ \theta=\dfrac{x}{\sqrt{x^2+h^2}}[/tex]

Now , from the figure :

[tex]2v_b=v_s\\\\2v_b=v_acos\ \theta\\\\v _a=\dfrac{2v_b}{cos\ \theta}\\\\v_a=\dfrac{2v_b\sqrt{x^2+h^2}}{x}[/tex]

Putting all given values in above equation :

[tex]v_a=\dfrac{2\times 3.03\times \sqrt{3.17^2+1.57^2}}{3.17}\\\\v_a=6.76\ m/s[/tex]

Therefore , value of [tex]v_a[/tex] is 6.76 m/s .

Hence , this is the required solution .

Ver imagen PhantomWisdom