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2 years ago

7

A 4-kg cat is resting on a bookshelf that is 2 m high. What is the cats gravitational potential energy relative to the floor if

the acceleration due to gravity is 9.8m/s^2?
a. 6 J
b. 8 J
c. 20 J
d. 78 J

1 answer:

ra1l [238]2 years ago

3 0

The most exact answer is 78.4J also in this kind of options we can say answer "d"

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Oksana_A [137]

Answer:9.75 m/s

Explanation:

Given

Length of ladder $(L)=5 m$

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From diagram

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at $x=3$

$y^2=25-9=16$

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Now differentiating equation 1 w.r.t time

$2x\frac{\mathrm{d} x}{\mathrm{d} t}+2y\frac{\mathrm{d} y}{\mathrm{d} t}=0$

$x\frac{\mathrm{d} x}{\mathrm{d} t}=-y\frac{\mathrm{d} y}{\mathrm{d} t}$

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$\frac{\mathrm{d} y}{\mathrm{d} t}=-\frac{3\times 13}{4}=-9.75 m/s$

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By what means can the internal energy of a closed system increase?.

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ArbitrLikvidat [17]

Answer:

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Answer

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speed of underneath wings = 234 m/s

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density of air = 1.29 kg/m³

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$P_1 + \dfrac{1}{2}\rho v_1^2 = P_2 + \dfrac{1}{2}\rho v_2^2$

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