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Greta is on the chairlift going up the mountain when one of her skis falls off.
The ski has a mass of 5 kg and hits the snow below with a speed of 72 km/h.
How high is the chairlift above the snow when the ski falls off?
(Ignore air resistance.)

Give your answer to the nearest 0.1 m.

Use g = 9.8 m/s2 for the acceleration due to gravity.

Respuesta :

Corsaquix

Answer:

[tex]20.4\:\text{m}[/tex]

Explanation:

We can use the following kinematics equation to find the height of the chairlift above the snow:

[tex]v_f^2=v_i^2+2a\Delta y[/tex].

First, let's convert 72 km/h to m/s:

[tex]72\: \text{km/h}=20\:\text{m/s}[/tex]

Since the ski starts with an initial vertical velocity of zero, we have [tex]v_i=0[/tex]. We can now substitute [tex]v_f=20,v_i=0, a=9.8[/tex] and solve for how high the chairlift is above the snow:

[tex]20^2=0^2+2\cdot9.8\cdot \Delta y,\\400=19.6\cdot \Delta y,\\\Delta y =\frac{400}{19.6}=\boxed{20.4\:\text{m}}[/tex].

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