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2 years ago

14

Lora (of mass 54 kg) is an expert skier. She

1 answer:

omeli [17]2 years ago

6 0

The mechanical energy at top =Mechanical energy at bottom

Mass=m=54kg
Height=h=51m
Acceleration due to gravity=g=10m/s^2
Velocity=v=2.6m/s

$\\ \tt\longmapsto M_{initial}=M_{Final}$

Final energy at bottom=The kinetic energy

$\\ \tt\longmapsto KE=M_{initial}$

$\\ \tt\longmapsto KE=P.E_{(Top)}+K.E_{(Top)}$

$\\ \tt\longmapsto K.E=mgh+\dfrac{1}{2}mv^2$

$\\ \tt\longmapsto K.E=m\left(gh+\dfrac{v^2}{2}\right)$

$\\ \tt\longmapsto K.E=54\left((10)(51)+\dfrac{2.6^2}{2}\right)$

$\\ \tt\longmapsto K.E=54\left(510+\dfrac{6.76}{2}\right)$

$\\ \tt\longmapsto K .E=54(510+3.38)$

$\\ \tt\longmapsto K.E=54(513.38)$

$\\ \tt\longmapsto K.E=27722.52J$

$\\ \tt\longmapsto K.E=27.7KJ$

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$\alpha = \frac{61.2 * 1.5 * 9.8}{15.975 + (61.2 ) * (1.5)^2}$

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$a = 5.854 * 1.5$

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$w = \frac{0.8892}{0.01667}$

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