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3 years ago

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A 2.0-kg mass is projected from the edge of the top of a 20-m tall building with a velocity of 24 m/s at some unknown angle abov

e the horizontal. Disregard air resistance and assume the ground is level. What is the kinetic energy of the mass just before it strikes the ground?

1 answer:

muminat3 years ago

6 0

Answer:

968 J

Explanation:

The computation of the kinetic energy is shown below:

Given that

mass m = 2 kg

height h = 20 m

velocity v = 24 m / s

Now

According to the law of conservation of energy ,

= K.E at top + P.E at top

= ( 1 ÷ 2) mv ^ 2 + mgh

= 576 + 392

= 968 J

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<u>Motion in The Plane</u>

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$\displaystyle y_m=v_o\ sin\theta \ \frac{v_o\ sin\theta }{g}-\frac{g}{2}\left (\frac{v_o\ sin\theta }{g}\right )^2$

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