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3 years ago

Have researchers have now been able to cool substances to absolute zero

1 answer:

6 0

It's a law of nature, which I don't understand too well, that we can
cool things as close to Absolute Zero as we want to, but we can
never get all the way there.

I think that individual atoms and molecules have been cooled in
the laboratory to within a few thousandths of a Celsius degree
of it ... actually not too shabby an accomplishment !
____________________________________

WOW ! I just went and searched online for more information
on this subject. (You can't imagine what great stuff you can find
by doing that. You ought to try it some time.)

The 1997 Nobel Prize in Physics was awarded to a team of three
physicists who invented a method of using lasers to slow down the
motion of atoms, and that's the same thing as cooling them. They
were able to cool some atoms to a temperature of 240 millionths
of a degree above Absolute Zero !

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I stretch a rubber band and "plunk" it to make it vibrate in its fundamental frequency. I then stretch it to twice its length an

Nikitich [7]

Answer:

The new frequency (F₂ ) will be related to the old frequency by a factor of one (1)

Explanation:

Fundamental frequency = wave velocity/2L

where;

L is the length of the stretched rubber

Wave velocity = $\sqrt{\frac{T}{\frac{M}{L}}}$

Frequency (F₁) = $\frac{\sqrt{\frac{T}{\frac{M}{L}}}}{2*L}$

To obtain the new frequency with respect to the old frequency, we consider the conditions stated in the question.

Given:

L₂ =2L₁ = 2L

T₂ = 2T₁ = 2T

(M/L)₂ = 0.5(M/L)₁ = 0.5(M/L)

F₂ = $\frac{\sqrt{\frac{2T}{0.5(\frac{M}{L})}}}{4*L} = \frac{\sqrt{4(\frac{T}{\frac{M}{L}}})}{4*L} = \frac{2}{2} [\frac{\sqrt{\frac{T}{\frac{M}{L}}}}{2*L}] = F_1$

Therefore, the new frequency (F₂ ) will be related to the old frequency by a factor of one (1).

7 0

2 years ago

A 4.00 m long, massless beam rests horizontally on a support 3.00 m from the left

Rus_ich [418]

If the beam is in static equilibrium, meaning the Net Torque on it about the support is zero, the value of x₁ is 2.46m

Given the data in the question;

Length of the massless beam; $L = 4.00m$

Distance of support from the left end; $x = 3.00m$

First mass; $m1 = 31.3 kg$

Distance of beam from the left end( m₁ is attached to ); $x_1 = ?$

Second mass; $m_2 = 61.7 kg$

Distance of beam from the right of the support( m₂ is attached to ); $x_1 = 0.273m$

Now, since it is mentioned that the beam is in static equilibrium, the Net Torque on it about the support must be zero.

Hence, $m_1g( x-x_1) = m_2gx_2$

we divide both sides by $g$

$m_1( x-x_1) = m_2x_2$

Next, we make $x_1$ , the subject of the formula

$x_1 = x - [ \frac{m_2x_2}{m_1} ]$

We substitute in our given values

$x_1 = 3.00m - [ \frac{61.7kg\ * \ 0.273m}{31.3kg} ]$

$x_1 = 3.00m - 0.538m$

$x_1 = 2.46m$

Therefore, If the beam is in static equilibrium, meaning the Net Torque on it about the support is zero, the value of x₁ is 2.46m

Learn more; brainly.com/question/3882839

6 0

3 years ago

Help me with this please

Marianna [84]

Answer:

<u>Family</u>

1. Definition of a family

A family is a group of people living together in a home related by blood, marriage or adoption.

2. Two function of the family are;

socialization for the children in the family.
love and happiness should be in a family for it to be function.

3. Two types of family are;

Single parent family- this family includes one parent and his or her child, we can say it's an incomplete family.
nuclear family- this family includes the two parents and their children or child, this family is known as the complete family.

4. Two roles and responsibilities of the parents and children in the home are;

both parents must and should protect their child or children from harm.
the children must have respect for the family.

<u>Accident in the Home</u>

1. Definition of accident in the home

accidents in the home are common to persons of all ages, therefore home accidents occurs in one's home that may cause an result an injury of a person

2. Two types of accident in the home

falls
minor cuts and wounds

3. The two uses of cereals in cooking

Cereals in cooking are used as thickened agents.

4. complete table

1. minor cuts and wounds

Causes: these are caused by broken glasses, contact with sharp instruments such as knife, pins and needles.
Prevention: this can be prevented by keeping the Sharp tools in safe places after used

2. Poisoning

Causes: poisoning can caused by in a result from children taking tablets for sweets, which can lead to death.
preventions: you can prevent this by avoiding poisoning from the from the home or you could put it at a safe place that you know the child cannot get it.

<u>Care labels</u>

1. definition of care label

care labels can be defined as a permanent label or we can say a tag, which contains regular instructions that is attached at the back of a cloth.

3. two classification of carbohydrates

Mono
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6 0

3 years ago

The slider of mass m is released from rest in position A and slides without friction along the vertical-plane guide shown. Deter

Anuta_ua [19.1K]

The value of normal force as the slider passes point B is

6 mg

The value of h when the normal force is zero

3R/2

<h3>How to solve for the normal force</h3>

The normal force is calculated using the work energy principle which is applied as below

K₁ + U₁ = K₂

k represents kinetic energy

U represents potential energy

the subscripts 1,2 , and 3 = a, b, and c

for 1 to 2

K₁ + W₁ = K₂

0 + mg(h + R) = 0.5mv²₂

g(h + R) = 0.5v²₂

v²₂ = 2g(1.5R + R)

v²₂ = 2g(2.5R)

v²₂ = 5gR

Using summation of forces at B

Normal force, N = ma + mg

N = m(a + g)

N = m(v²₂/R + g)

N = m(5gR/R + g)

N = 6mg

for 1 to 3

K₁ + W₁ = K₃ + W₃

0 + mgh = 0.5mv²₃ + mgR

gh = 0.5v²₃ + gR

0.5v²₃ = gh - gR

v²₃ = 2g(h - R)

at C

for normal force to be zero

ma = mg

v²₃/R = g

v²₃ = gR

and v²₃ = 2g(h - R)

gR = 2gh - 2gR

gR + 2gR = 2gh

3gR = 2gh

3R/2 = h

Learn more about normal force at:

brainly.com/question/20432136

#SPJ1

8 0

10 months ago

Compare the forces in a small nucleus to the forces in a large nucleus

pochemuha

The comparison of the forces in a small nucleus to the forces of a large one is the fact that they are capable of holding the protons and neutrons which made it no matter what their size may be. Therefore, as long as there is a nucleus, their forces can both hold together the two atoms tight.

6 0

3 years ago