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3 years ago

The north and south poles of a magnetic field produced by an electromagnet will switch when the direction of the changes.

Physics

2 answers:

baherus [9]3 years ago

4 0

Explanation :

An electromagnet has a coil of wire which is wrapped around an iron core. When an electric current is passed over it, it behaves like a magnet.

For DC current,

When the direction of current is reversed in an electromagnet, its poles gets reversed.

For AC current,

AC or alternating current continuously changes the direction of the current. So, the north poles and south poles keep on changing.

So, the north and south poles of a magnetic field produced by an electromagnet will switch when the direction of the current changes.

Aneli [31]3 years ago

3 0

When the direction of the current changes

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What is the average translational KE of 5 moles of gas molecules at 300 K?

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Answer:

What is the average translational kinetic energy of molecules in an ideal gas at 37°C? The average translational energy of a molecule is given by the equipartition theorem as, E = 3kT 2 where k is the Boltzmann constant and T is the absolute temperature.

Explanation:

The average translational energy of a molecule is given by the equipartition theorem as, E = 3kT 2 where k is the Boltzmann constant and T is the absolute temperature.

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3 years ago

What is the relationship between wavelength and the amount of energy the wave carries?

nadezda [96]

Answer:

Energy is inversely proportional to wavelength.

Explanation:

The amount of energy, E, a wave carries is given as:

E = hf

where h = Planck's constant and f = frequency of the wave

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c = λf

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4 years ago

Numerical Problems

Evgesh-ka [11]

Answer:

a = 5 [m/s²]

Explanation:

To solve this problem we must use the following equation of kinematics.

$v_{f}=v_{o}+a*t$

where:

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3 years ago

A spaceship starting from a resting position accelerates at a constant rate of 9.8 meters per second per second. How long and ho

Verizon [17]

Accelerating at 9.8 m/s² means that every second, the speed is 9.8 m/s faster than it was a second earlier. It's not important to the problem, but this number (9.8) happens to be the acceleration of gravity on Earth.

1% of the speed of light = (300,000,000 m/s) / 100 = 3,000,000 m/s .

Starting from zero speed, moving (9.8 m/s) faster every second,
how long does it take to reach 3,000,000 m/s ?

   (3,000,000 m/s) / (9.8 m/s²) = 306,122 seconds .
   (That's 5,102 minutes.)
(That's 85 hours.)
   (That's 3.54 days.)

Speed at the beginning . . . zero .
Speed at the end . . . 3,000,000 m/s
Average speed . . . . . 1,500,000 m/s

Distance = (average speed) x (time)

   = (1,500,000 m/s) x (306,122 sec) = 4.592 x 10¹¹ meters

   = 459 million kilometers

   That's like from Earth
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3 years ago

A horizontal circular platform (m = 119.1 kg, r = 3.23m) rotates about a frictionless vertical axle. A student (m = 54.3kg) walk

Murrr4er [49]

Answer:

$\omega_2=5.1rad/s$

Explanation:

Since there is no friction angular momentum is conserved. The formula for angular momentum thet will be useful in this case is $L=I\omega$ . If we call 1 the situation when the student is at the rim and 2 the situation when the student is at $r_2=1.39m$ from the center, then we have:

$L_1=L_2$

Or:

$I_1\omega_1=I_2\omega_2$

And we want to calculate:

$\omega_2=\frac{I_1\omega_1}{I_2}$

The total moment of inertia will be the sum of the moment of intertia of the disk of mass $m_D=119.1 kg$ and radius $r_D=3.23m$ , which is $I_D=\frac{m_Dr_D^2}{2}$ , and the moment of intertia of the student of mass $m_S=54.3kg$ at position $r$ (which will be $r_1=r=3.23m$ or $r_2=1.39m$ ) will be $I_{S}=m_Sr_S^2$ , so we will have: