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4 years ago

Why were epicycles necessary in ptolemy’s model of the universe?

2 answers:

N76 [4]4 years ago

4 0

Because Mars, Jupiter, and Saturn each appear to slow down, stop, move backwards for a while, then again slow down, stop, and start moving forward again. Each plant does this at some time during each year.

If they were simply moving in circles around the Earth, they couldn't do any of this. They would need to be moving on small circles attached to the big circles. The small ones are the 'epicycles'.

Liono4ka [1.6K]4 years ago

3 0

epicycles were orbits within orbits used to explain discrepancies between expected and observed planetary movement, including the appearance of planets slowing down, speeding up, and moving backward.

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If a satellite moves with constant speed in a perfectly circular orbit around the earth, what is the direction of the accelerati

9966 [12]

Traveling at any point on a curve, the force and the acceleration are toward
the center of the circle that the curve is part of. On a perfectly circular path,
the force and acceleration are always toward the center of the circle.

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3 years ago

A water-skier is moving at a speed of 12.0 m/s . When she skis in the same direction as a traveling wave, she springs upward eve

Kisachek [45]

Answer:

Mechanical waves require a medium to transfer their energy.

What are examples of mechanical waves?

Explanation:

Mechanical waves require a medium to transfer their energy.

What are examples of mechanical waves?

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3 years ago

The areas of the continents that are under shallow water are

Sunny_sXe [5.5K]

Answer:

costal areas

Explanation:

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3 years ago

What color is iodine solid and its gas?

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Purple -non black metallic

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3 years ago

A loop of wire is in a magnetic field such that its axis is parallel with the field direction. Which of the following would resu

ahrayia [7]

Answer:

All the given options will result in an induced emf in the loop.

Explanation:

The induced emf in a conductor is directly proportional to the rate of change of flux.

$emf = -\frac{d \phi}{dt} \\\\where;\\\\\phi \ is \ magnetic \ flux\\\\\phi = BA\ cos \theta$

where;

A is the area of the loop

B is the strength of the magnetic field

θ is the angle between the loop and the magnetic field

Considering option A, moving the loop outside the magnetic field will change the strength of the magnetic field and consequently result in an induced emf.

Considering option B, a change in diameter of the loop, will cause a change in the magnetic flux and in turn result in an induced emf.

Option C has a similar effect with option A, thus both will result in an induced emf.

Finally, considering option D, spinning the loop such that its axis does not consistently line up with the magnetic field direction will change the angle between the loop and the magnetic field. This effect will also result in an induced emf.

Therefore, all the given options will result in an induced emf in the loop.

4 0

3 years ago