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Fleur Delacour spies the golden egg behind the Common Welsh Green. She places a 0.6 kg vial Sleeping Draught on a rough patch of grass with a coefficient of friction 0.35 in a bungee sling (51.6 N/m . Fleur pulls the sling to the left 1.2 m and releases the vial.The vial travels across the grass and slides across an icy path for 17m. If the dragon is stalking toward the golden egg at 19.5 m/s, will the Draught overtake it and let Fleur secure the win?

1 Answer

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To determine if the Draught will overtake the dragon, we need to compare their speeds. The calculated speed of the Draught is -6.906 m/s, while the dragon is moving at 19.5 m/s. Therefore, the Draught will not overtake the dragon and Fleur will not secure the win.

In order to determine if the Draught will overtake the dragon, we need to compare their speeds. First, let's determine the speed of the Draught on the rough patch of grass:

Force of friction (Ff) = coefficient of friction (μ) * normal force (Fn)

Ff = 0.35 * (0.6 kg * 9.8 m/s²) = 2.058 N

Net force (Fnet) = Fd - Ff

Fnet = (51.6 N/m)(1.2 m) - 2.058 N = 59.52 N - 2.058 N = 57.462 N

Acceleration (a) = Fnet / m

a = 57.462 N / 0.6 kg = 95.77 m/s²

Now, let's calculate the distance the Draught travels on the icy path:

Use the kinematic equation: x = vot + (1/2)at²

17 m = 0 + (1/2)(-1.4 m/s²)(t)²

t = √(34 / 1.4) = √24.2857 ≈ 4.928 s

Finally, let's find the final velocity of the Draught:

v = vo + at

v = 0 + (-1.4 m/s²)(4.928 s) = -6.906 m/s

Since the dragon is moving at a speed of 19.5 m/s and the Draught has a speed of -6.906 m/s, the Draught will not overtake the dragon and Fleur will not secure the win.

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