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3 years ago

if you put something like apiece of cardboard between a magnet and a iron nail, the magnet still holds the nail. how?

1 answer:

8 0

Magnetic fields can go through some materials (like cardboard). Electric fields can also do that. Electromagnetic waves can do that. It’s not at all unusual because magnetic fields are not made up of particles so they can go through materials.

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In the reaction _S+302 +2SO3, what coefficient should be placed in front of the S to balance the reaction?

lys-0071 [83]

Answer:

B. 2

Explanation:

The reaction expression is given as:

_S + 3O₂ → 2SO₃

Now let us balanced the expression;

On the product side we have 2 moles of S

On the reactant side we should have 2moles of S

So, we put the coefficient 2 to balance the expression;

We have 6 moles oxygen on both sides

5 0

3 years ago

A single loop of wire with an area of 0.0780 m2 is in a uniform magnetic field that has an initial value of 3.80 T, is perpendic

Katarina [22]

Answer:

The induced current is 26.7 mA

Explanation:

Given;

area of the loop, A = 0.078 m²

initial magnetic field, B₁ = 3.8 T

change in the magnetic field strength, dB/dt = 0.24 T/s

The induced emf is calculated as;

$emf = - \frac{d \phi}{dt} \\\\emf = -\frac{dB.A}{dt} \\\\emf = A (\frac{dB}{dt} )\\\\emf = 0.078(0.24)\\\\emf = 0.0187 \ V$

The resistance of the loop = 0.7 Ω

The induced current is calculated as;

$V = IR\\\\I = \frac{V}{R} = \frac{emf}{R} = \frac{0.0187}{0.7} = 0.0267 \ A = 26.7 \ mA$

4 0

3 years ago

A mountain climber, in the process of crossing between two cliffs by a rope, pauses to rest. She weighs 514 N. As the drawing sh

n200080 [17]

Answer:

Part a)

$T_L = 155.4 N$

Part b)

$T_R = 379 N$

Explanation:

As we know that mountain climber is at rest so net force on it must be zero

So we will have force balance in X direction

$T_L cos65 = T_R cos80$

$T_L = 0.41 T_R$

now we will have force balance in Y direction

$mg = T_L sin65 + T_Rsin80$

$514 = 0.906T_L + 0.985T_R$

Part a)

so from above equations we have

$514 = 0.906T_L + 0.985(\frac{T_L}{0.41})$

$514 = 3.3 T_L$

$T_L = 155.4 N$

Part b)

Now for tension in right string we will have

$T_R = \frac{T_L}{0.41}$

$T_R = 379 N$

3 0

3 years ago

What is reflection? Reflection is light that has struck a surface and has __________. .

Bad White [126]

The correct answer should be bounced off since the light ray hit the surface and reflected towards a new location. It therefore bounced off.

8 0

3 years ago

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A surface receiving sound is moved from its original position to a position three times farther away from the source of the soun

murzikaleks [220]

As long as all the waves stay in the same medium, the intensity of
any waves ... electromagnetic or mechanical ... decrease in proportion
to the square of the distance.

If the distance increases to 3 x the original distance, then the intensity
changes to 1/3² or 1/9 of the original intensity.

I suppose choice-'d' is the correct one, but I have to tell you that
the phrase "nine times as low" is mathematically meaningless,
and it really grinds my gears.

5 0

3 years ago

Read 2 more answers