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2 years ago

12

A 65 kg box is lifted by a person pulling a rope a distance of 15 meters straight up at a constant speed. How much Power is requ

ired from the person in order to complete this task in 9 seconds?
__ Watts

1 answer:

Y_Kistochka [10]2 years ago

8 0

Answer:

Power is 1061.67W

Explanation:

Power=force×distance/time

Power=65×9.8×15/9 assuming gravity=9.8m/s²

Power=3185/3=1061.67W

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In Rutherford's experiment, which of the following proved that the

vampirchik [111]

Answer:

b) the alpha particles were found to be attracted to the nucleus

Explanation:

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2 years ago

What is the final speed of a 60 kg boulder dropped from a 111 meter cliff

saveliy_v [14]

After rolling off the edge of the cliff and falling ' M ' meters down,
the speed of the boulder is

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2 years ago

An airliner arrives at the terminal, and its engines are shut off. The rotor of one of the engines has an initial clockwise angu

Ilia_Sergeevich [38]

(a) 1200 rad/s

The angular acceleration of the rotor is given by:

$\alpha = \frac{\omega_f - \omega_i}{t}$

where we have

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Solving for $\omega_f$ , we find the final angular speed after 10.0 s:

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(b) 25 s

We can calculate the time needed for the rotor to come to rest, by using again the same formula:

$\alpha = \frac{\omega_f - \omega_i}{t}$

If we re-arrange it for t, we get:

$t = \frac{\omega_f - \omega_i}{\alpha}$

where here we have

$\omega_i = 2000 rad/s$ is the initial angular speed

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2 years ago

The vector position of an object is given by r what is the torque acting on the object about the origin when a force f = (−12.5i

attashe74 [19]

Let the vector position of the object in the (x-y) plane be
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The applied force is
$\vec{f} = -12.5 \hat{i}
$

By definition, the applied torque is
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3 years ago

Scientists study how the continents move. Why might scientists use a model

tigry1 [53]

Answer:

B. It is too slow to observe directly

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I hope it helps! Have a great day!
bren~

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1 year ago