In the winter activity of tubing, riders slide down snow covered slopes while sitting on large inflated rubber tubes. To get to the top of the slope, a rider and his tube, with a total mass of 88 kgkg , are pulled at a constant speed by a tow rope that maintains a constant tension of 350 NN .
How much thermal energy is created in the slope and the tube during the ascent of a 30-m-high, 120-m-long slope?

Respuesta :

Answer:

16.10 kJ

Explanation:

The thermal energy created in the slope can be found by definition of work (W):  

[tex] W = E_{f} - E_{i} = K_{f} + P_{f} + Th_{f} - (K_{i} + Th_{i}) [/tex]

Where:

[tex]K_{f}[/tex] and [tex]K_{i}[/tex]: is the final and initial kinetic energy

[tex]P_{f}[/tex]: is the final potential energy

[tex]Th_{f}[/tex] and [tex]Th_{i}[/tex]: is the final and initial thermal energy

[tex]W = \frac{1}{2}mv_{f}^{2} + mgh - \frac{1}{2}mv_{i}^{2} + Th_{f} - Th_{i}[/tex]

We have that W is:

[tex] W = F*d = T*d [/tex]

Where:

F: is the force equal to the tension (T)

d: is the displacement = 120 m

And since the speed is constant, [tex]v_{i}[/tex] = [tex]v_{f}[/tex] we have:

[tex] T*d = mgh + \Delta Th [/tex]

[tex] \Delta Th = T*d - mgh = 350 N*120 m - 88 kg*9.81 m/s^{2}*30 m = 16101.6 J [/tex]

Therefore, the thermal energy created in the slope and the tube during the ascent is 16.10 kJ.

I hope it helps you!  

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