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3 years ago

9

You are holding a 1 kg rock and standing at the top of a cliff. You drop the rock off the cliff and it falls a distance 10 m. In

this problem, you can ignore air resistance.
What is the change in the kinetic energy of the rock as it falls that distance?

1 answer:

vfiekz [6]3 years ago

7 0

Answer:

98J

Explanation:

Given that the mass of the rock m=1kg, the height =10m and we know that gravitational force is $g=9.8N/kg$ .

Change in kinetic energy happens when the initial potential energy at rest is converted into Kinetic energy as:

$\bigtriangleup KE=\bigtriangleup mgh\\\\=1kg\times 9.8\times10m\\\\=98J$

Hence, the change in kinetic energy of the rock is 98J

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Expanding the vector sum, we get

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