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3 years ago

Why the electric bell will not work if the Electromagnet is replaced with a permanent magnet?

2 answers:

5 0

As electromagnet are temporary magnets so we can easily change its properties. An electric bell uses an electromagnet which is not a permanent magnet.So the given statement in the problem that a permanent magnet is used in an electric bell is false

maksim [4K]3 years ago

5 0

Electromagnets are temporary magnets. It is composed of a metal core and a loop of coil around it. It acts as a magnet when there is a current running through the coil and acts nothing if there is no current running through the coil.

You might be interested in

How does geomagnetism help scientist understand the motion of earth’s plates?

xeze [42]

Answer:

As the "plates" on each side of ridges in the seafloor are pulled away, lava comes up from the middle, hardens and "records" the current magnetic field.

Explanation:

6 0

3 years ago

Four different resistors have various amounts of electric current flowing through them. Given the values of current I and resist

Artemon [7]

You did not provide the options. However, the options are

I = 6.0, R= 4.0 ohms

I = 9.0, R= 2.0ohms

I = 3.0, R= 2.0ohms

I = 8.0, R= 8.0 ohms

Answer:

The order of the resistors from the highest to the lowest is:

I = 8.0, R= 8.0 ohms

I = 6.0, R= 4.0 ohms

I = 9.0, R= 2.0ohms

I = 3.0, R= 2.0 ohms

Explanation:

ohm's law states that voltage across a conductor is directly proportional to the current flowing through it. V = IR

Based on this formula, the voltages in each of the resistors are calculated below from the highest to the lowest

For I = 8.0, R= 8.0 ohms

V = 8 * 8 =64 volts

For I = 6.0, R= 4.0 ohms

V = 6 * 4 =24 volts

For I = 9.0, R= 2.0 ohms

V = 9 * 2 =18 volts

For I = 3.0, R= 2.0 ohms

V = 3 * 2 =6 volts

3 0

3 years ago

The 0.15kg baseball has a speed of v=30 m/s just before it is struck by the bat. It then travels along the trajectory shown befo

notka56 [123]

The magnitude of the average impulsive force imparted to the ball if it is in contact with the bat is 6000 N

The mass of the baseball, m = 0.15 kg

The speed at which it moves, v = 30 m/s

Time at which the baseball was in contact with the bat, t = 0.75 ms

t = 0.75/1000 s

t = 0.00075 s

The impulsive force is given by the formula:

$F=\frac{mv}{t}$

Substitute m = 0.15 kg, v = 30, and t = 0.00075s into the formula above:

$F=\frac{0.15 \times 30}{0.00075} \\\\F=6000N$

The magnitude of the average impulsive force imparted to the ball if it is in contact with the bat is 6000 N

Learn more here: brainly.com/question/25892144

4 0

2 years ago

Which requires more work, carrying a 420 N knapsack up a 200 m hill or carrying a 210 knapsack up a 400 m hill? Why?

Katen [24]

Answer:

Explanation:

because the weight/work increases bcz of the time period

4 0

4 years ago

You're at rest in a hammock when a hungry mosquito sees an opportunity for lunch. A mild 2 m/s breeze is blowing. If the mosquit

valentinak56 [21]

Answer:

A) against the breeze at 2 m/s

Explanation:

Given that air is blowing at 2 m/s.An a mosquito eat lunch.If mosquito want to eat lunch he have to move opposite to the direction of air because air is blowing at 2 m/s.So we can say that mosquito have to move against the air.

But in we have to protect our self from mosquito because if any mosquito bite us then it may lead to fever .So the protection is very important from mosquito .

Therefore the answer is --

6 0

3 years ago