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2 years ago

To a nighttime observer on Earth, how many degrees do the stars appear to move around Polaris in 3 hours?

1 answer:

5 0

<span>The correct answer is 45 degrees. 360 degrees is 24 hours, because it takes a whole day for the earth to turn in one whole circle. So, to find how many degrees the stars seem to move per hour, simply divide the total number of degrees by the total number of hours in a day: 360/24 = 15. Since the question is asking how much the stars appear to move in 3 hours, now multiply the number of degrees per hour times 3: 15 x 3 = 45. </span>

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The charge on an electron is −1.6×10−19 C. The charge on a proton is equal in magnitude, but positive. The electron's mass is 9.

prisoha [69]

A) The acceleration of the electron is $1.0\cdot 10^{23} m/s^2$ towards the proton

B) The electric field magnitude at the electron's location is $5.76\cdot 10^{11} N/C$

C) 2. The electric field in an atom is much greater than the dielectric strength of air

Explanation:

In order to find the acceleration of the electron, we need to find the force acting on it first.

The force on the electron is the electrostatic force between the proton and the electron, which is given by:

$F=k\frac{q_1 q_2}{r^2}$

where:

$k=8.99\cdot 10^9 Nm^{-2}C^{-2}$ is the Coulomb's constant

$q_1 = 1.6\cdot 10^{-16}C$ is the charge of the proton

$q_2 = -1.6\cdot 10^{-19}C$ is the charge of the electron

$r=5.0\cdot 10^{-11}m$ is the distance between the electron and the proton

Substituting,

$F=(8.99\cdot 10^9) \frac{(1.6\cdot 10^{-19})(-1.6\cdot 10^{-19})}{(5.0\cdot 10^{-11})^2}=-9.2\cdot 10^{-8} N$

where the negative sign indicates the direction of the force is towards the proton (attractive).

Now we can find the acceleration of the electron using Newton's second law:

$a=\frac{F}{m}$

where

F is the force

$m=9.11\cdot 10^{-31} kg$ is the electron mass

Substituting,

$a=\frac{-9.2\cdot 10^{-8}}{9.11\cdot 10^{-31}}=-1.0\cdot 10^{23} m/s^2$

where the negative sign means the direction is towards the proton.

The magnitude of the electric field due to a single-point charge is given by

$E=k\frac{q}{r^2}$

where

$k=8.99\cdot 10^9 Nm^{-2}C^{-2}$ is the Coulomb's constant

q is the charge

r is the distance from the charge at which the field is calculated

Here we have:

$q=1.6\cdot 10^{-19}C$ (proton charge)

$r=5.0\cdot 10^{-11} m$ (location of the electron with respect to the proton)

Therefore, the magnitude of the electric field is

$E=(8.99\cdot 10^9)\frac{1.6\cdot 10^{-19}}{(5.0\cdot 10^{-11})^2}=5.76\cdot 10^{11} N/C$

The electric field at which the air begins to spark is

$E_b = 3\cdot 10^6 N/C$

While the electric field in the atom (at the location of the electron), calculated in part B, si

$E=5.76\cdot 10^{11} N/C$

By comparing the two fields, we observe that

$E_b$

which means that the correct statement is

2. The electric field in an atom is much greater than the dielectric strength of air

Learn more about atoms:

brainly.com/question/2757829

#LearnwithBrainly

6 0

3 years ago

The change in electric potential energy per unit charge is

klemol [59]

D-Volatge / gravity and current aren’t units and amperes is the loop of electrical current

6 0

2 years ago

Read 2 more answers

Which statement correctly describes sound waves

Alexxandr [17]

Answer:

Sound waves are longitudinal waves

Explanation:

Sound waves are the longitudinal waves. In longitudinal waves, the particles of the wave move parallel to the direction of propagation of waves.

It moves in the form of compression and rarefaction. When the particles are compact in a space the compression occurs while when they far apart form each other rarefaction occurs.

3 0

2 years ago

Explain in your own words the interaction between the electric and magnetic fields that make up a light wave.

iVinArrow [24]

Answer:

They oscillates perpendicularly to one another, the oscillation of one field generates the other field.

Explanation:

In a light wave, an oscillating electric field of a light wave produces a magnetic field, and the magnetic field also oscillates to produce an electric field. The magnetic field and the electric field of a light wave both oscillates perpendicularly to one another. The resultant energy and direction of the wave generated as a result of these oscillating fields is propagated perpendicularly to both fields.

8 0

2 years ago

While John is traveling along a straight interstate highway , he notices that the mile marker reads 248 km. John travels until h

sergiy2304 [10]

Answer:

I'm just going to tell you the information you need but not the answer so you can learn from the problem.

Explanation:

So he was at 248 km mark and traveled 99 km to get to the 149km mark. Then he turns around to go back 18 km to the 167 km mark. That is all the information you need to complete the question I recommend drawing it out in your notes.

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2 years ago