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3 years ago

What is latent heat of fusion?

2 answers:

6 0

There's two forms of latent heat, there's latent heat of fusion which is melting, and there's latent heat of vaporization which is boiling. They describe the direction of energy flow when changing from one thing to the next like solid to liquid, or liquid to gas.

Naddik [55]3 years ago

5 0

If you have a lump of solid at its melting point ... like ice at 32°F ...
you have to put a certain amount of heat into it just to change it
to water at 32°F. That amount of heat, that's used just to change
a solid lump into liquid without changing its temperature, is called
the heat of fusion for that substance.

The number is different for every substance.

For water, it takes 336 joules of heat to melt 1 gram of ice
into 1 gram of water, all at 32°F (0°C).
That's an enormous latent heat of fusion ... more than almost any
other known substance. That's why ice is such a good choice
when you need something to put in your drink to cool it down.
Ice absorbs a huge amount of heat before it melts and the drink
gets watered down.

You might be interested in

You extend an impromptu invitation to a friend for dinner. The only food you have is a couple of frozen steaks. You wish to defr

kakasveta [241]

Answer:

Microwave: Radiation

Water: Conduction, convection & radiation.

Explanation:

When we heat a food using microwave then the water content of the food is only heated by the microwave.

Microwaves make the molecules of water vibrate frequently with a frequency closer to the frequency of microwaves and this increases the kinetic energy of the molecules which produces heat in the water molecules this heat then propagates to the whole food by conduction and convection, but the heat enters the food only via radiation.

Now when the food item is kept into warm water then the molecules closer to the food heat the food by conduction through direct energy transfer by lattice vibrations and when they become cooler than the mass of water all around then due to density difference they settle down and their place is occupied by warmer molecules around in the fluid leading to convection.

Radiation of energy from a mass occurs continuously irrespective of the medium present there. So the heat of water also enters the food by radiation of energy from the water molecules.

3 0

3 years ago

The vacuum tube was replaced with what electrical component?

Rufina [12.5K]

Answer:

The vacuum tube was replaced with transistor.

Explanation:

The invention of semiconductor was very useful in making solid state transistor that allowed the production of small yet faster, cheaper, and more trusted and reliable computers.
These solid state transistor is so often used that, it nearly replaced all the use of transistor.
This replacement took place after the invention of semiconductor in the year around 1940.
Vacuum tubes also known as thermionic tubes are not used anymore in computers and electronics.

7 0

3 years ago

ASAP describe how energy is transferred in a mechanical wave

kirill115 [55]

A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one

8 0

3 years ago

Electrons are ejected from sodium metal by any light that has a wavelength shorter than 544 nm. What is the kinetic energy of an

wel

Answer:

KE=2.3 x 10⁻¹⁹ J

Explanation:

Given that

λ = 544 nm

λ' = 485 nm

The kinetic energy KE given as

KE= E - Ф

Where

$E=\dfrac{hC}{\lambda'}$

$\phi=\dfrac{hC}{\lambda}$

h= 6.626 x 10⁻³⁴

C=3 x 10⁸ m/s

Now by putting the values

$KE=\dfrac{hC}{\lambda'}-\dfrac{hC}{\lambda}$

$KE=\dfrac{34.34\times 10^{-34}\times 3\times 10^8}{485\times 10^{-9}}- \dfrac{34.34\times 10^{-34}\times 3\times 10^8}{544\times 10^{-9}}$

KE=2.3 x 10⁻¹⁹ J

This is kinetic energy.

6 0

3 years ago

If a car moving at 15 m/s skids to a stop after 20 m, how far will it skid if it is moving at 45 m/s? Assume that the braking fo

kaheart [24]

The car will skid at 80m

As we know that In mechanics, acceleration is the rate of change of the velocity of an object with respect to time.

It is a vector quantity

The velocity is the distance covered by an object per unit time

Given

Initial velocity (u) = 15m/s

Final Velocity (v) = 0m/s

Distance (s) = 20 m

Deceleration (a) =?

Now we know that ,

v² = u² + 2as

Substituting the value

0² = 15² + (2)*(a)*(20)

0 = 225 + 40a

Collecting the like terms

0 – 235 = 40a

–225 = 40a

To find the value of a divide both side 40

a = –225 / 50

a = –5.625 m/s²

Determination of the distance

Deceleration (a) = –5.625 m/s²

Initial velocity (u) = 30 m/s

Final velocity (v) = 0 m/s

Distance (s) =?

v² = u² + 2as

0² = 30² +(2 × –5.625 × s)

0 = 900 – 11.25s

Collecting like terms

0 – 900 = –11.25s

–900 = –11.25s

To find the value of s divide both side by –11.25

s = –900 / –11.25

s = 80 m

Hence the car will skid 80 m

Learn more about motion here :

brainly.com/question/453639

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6 0

2 years ago