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3 years ago

a 2.80 kg mass is dropped from a height of 4.50 m. find its potential energy(PE) at the moment it is dropped. PLEASE HELP

Physics

1 answer:

Maurinko [17]3 years ago

4 0

Answer:

126 J

Explanation:

The potential energy only depends on the vertical height from the ground level.

We consider the ground level to have zero P.E.

We get, when it is 4.5 m above the ground level,

P.E. = mgh

= 2.8×10×4.5

= 126 J

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Answer:

a) -35.6°C

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Explanation:

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$\begin{gathered} T_c=\frac{5}{9}(-32-32) \\ \\ T_c=\frac{5}{9}(-64) \\ \\ T_c=-35.6^0C \end{gathered}$

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1 year ago

An elevator car has a mass of 750 kg, and its three passengers have a combined mass of 135 kg. If the elevator and its passenger

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Answer:

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Explanation:

The change in gravitational potential energy is given by:

$\Delta E_{p} = E_{p_{f}} - E_{p_{i}}$

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Where:

"i" is for final and "f" for final

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For the car and the passengers we have:

$\Delta E_{p} = m_{T}g(h_{f} - h_{i}) = (750 kg + 135 kg)9.81 m/s^{2}(0 - 20.7 m) = -1.80 \cdot 10^{5} J$

The minus sign is because when the elevator car and the passengers are up they have a bigger gravitational potential energy than when they are in the ground.

Therefore, the change in gravitational potential energy is -1.80x10⁵ J.

I hope it helps you!

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3 years ago

A skillet is removed from an oven whose temperature is 450°F and placed in a room whose temperature is 70°F. After 5 minutes, th

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Answer:

attached below

Explanation:

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3 years ago

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Answer:

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Explanation:

Given :

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3 years ago

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Answer:

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3 years ago

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