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2 years ago

Arrange the objects in order from least to greatest potential energy. Assume that gravity is constant. (Use PE = m × g × h.)

Physics

2 answers:

yawa3891 [41]2 years ago

8 0

Answer:The objects in order from least to greatest potential energy:

3<1<4<2

Explanation:

1. Potential energy of a 15-kilogram stone found at a height of 3 meters:

$mgh=15 kg\times 9.8 m/s^2\times 3 m=441 J$

2. Potential energy 10 kilograms of water stored at a height of 9 meters:

$mgh=10 kg\times 9.8 m/s^2\times 9 m=882 J$

3. Potential energy 1-kilogram ball located 20 meters in the air:

$mgh=1 kg\times 9.8 m/s^2\times 20 m=196 J$

4. Potential energy box of books weighing 25 kilograms placed on a shelf 2 meters high:

$mgh=25 kg\times 9.8 m/s^2\times 2 m=490 J$

The objects in order from least to greatest potential energy:

3<1<4<2

Novosadov [1.4K]2 years ago

3 0

Answer:

the answer is 2. 4. 1. 3.

Explanation:

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where

$q=0.500 \mu C = 0.500\cdot 10^{-6} C$ is the charge on the plane

v = 660 m/s is the velocity

$B=8.00\cdot 10^{-5} T$ is the magnitude of the magnetic field

$\theta=90^{\circ}$ is the angle between the direction of motion of the jet and of the magnetic field

Substituting,

$F=(0.5\cdot 10^{-6})(660)(8.0\cdot 10^{-5})=2.64\cdot 10^{-8} N$

The direction can be found by using Fleming's left hand rule. We have:

- index finger: magnetic field direction (straight up)

- middle finger: velocity of the plane (due west)

- force: thumb --> north

(b) Not negligible

As we can see from part (a), the magnitude of the force is not really big, so the effects are negligible.

For instance, we can compare this force with the weight of a plane. If we take a Boeing 737, its mass is about 80,000 kg, so its weight is

$W=mg=(80000)(9.8)=784,000 N$

As we can see, this is several orders of magnitude bigger than the magnetic force calculated at point (a), so the effects of the magnetic force are negligible.

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2 years ago

The second law of thermodynamics states that whenever energy changes occur, __________ always increases.

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The second law of thermodynamics states that whenever energy changes occur, DISORDER always increases.

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2 years ago

A solution is oversaturated with solute. Which could be done to decrease the oversaturation?

salantis [7]

Ans: Dilute the solution

Explanation:
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2 years ago

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A 17 g audio compact disk has a diameter of 12 cm. The disk spins under a laser that reads encoded data. The first track to be r

sladkih [1.3K]

Answer:

0.00066518 Nm

Explanation:

v = Velocity = 1.2 m/s

r = Distance to head = 2.3 cm

$\omega_f$ = Final angular velocity

$\omega_i$ = Initial angular velocity = 0

$\alpha$ = Angular acceleration

t = Time taken = 2.4 s

Angular speed is given by

$\omega=\dfrac{v}{r}\\\Rightarrow \omega=\dfrac{1.2}{0.023}\\\Rightarrow \omega=52.17391\ rad/s$

From equation of rotational motion

$\omega_f=\omega_i+\alpha t\\\Rightarrow \alpha=\frac{\omega_f-\omega_i}{t}\\\Rightarrow \alpha=\frac{52.17391-0}{2.4}\\\Rightarrow \alpha=21.73912\ rad/s^2$

Torque

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2 years ago

Which changes in an electric motor will make the motor stronger? Check all that apply.

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