About how many times greater is the density of a neutron star compared to a white dwarf?

The soccer game begins with a ______ ______ in the center of the field

blagie [28]

It begins with a kick-off

6 0

3 years ago

Consider a container of oxygen gas at a temperature of 23°C that is 1.00 m tall. Compare the gravitational potential energy of a

Sergio039 [100]

Answer:

Yes, it is reasonable to neglect it.

Explanation:

Hello,

In this case, a single molecule of oxygen weights 32 g (diatomic oxygen) thus, the mass of kilograms is (consider Avogadro's number):

$m=1molec*\frac{1mol}{6.022x10^{23}molec} *\frac{32g}{1mol}*\frac{1kg}{1000g}=5.31x10^{-26}kg$

After that, we compute the potential energy 1.00 m above the reference point:

$U=mhg=5.31x10^{-26}kg*1.00m*9.8\frac{m}{s^2}=5.2x10^{-25}J$

Then, we compute the average kinetic energy at the specified temperature:

$K=\frac{3}{2}\frac{R}{Na}T$

Whereas $N_A$ stands for the Avogadro's number for which we have:

$K=\frac{3}{2} \frac{8.314\frac{J}{mol*K}}{6.022x10^{23}/mol}*(23+273)K\\ \\K=6.13x10^{-21}J$

In such a way, since the average kinetic energy energy is about 12000 times higher than the potential energy, it turns out reasonable to neglect the potential energy.

Regards.

8 0

4 years ago

What is a break in rock? Science

Kaylis [27]

Its physical weathering and physical weathering can be sometimes called mechanical weathering it includes the processes which break rocks apart changing their chemical composition.

3 0

3 years ago

A man is standing on a weighing machine on a ship which is bobbing up and down with simple harmonic motion of period T=15.0s.Ass

STALIN [3.7K]

Well, first of all, one who is sufficiently educated to deal with solving
this exercise is also sufficiently well informed to know that a weighing
machine, or "scale", should not be calibrated in units of "kg" ... a unit
of mass, not force. We know that the man's mass doesn't change,
and the spectre of a readout in kg that is oscillating is totally bogus.

If the mass of the man standing on the weighing machine is 60kg, then
on level, dry land on Earth, or on the deck of a ship in calm seas on Earth,
the weighing machine will display his weight as 588 newtons or as
132.3 pounds. That's also the reading as the deck of the ship executes
simple harmonic motion, at the points where the vertical acceleration is zero.

If the deck of the ship is bobbing vertically in simple harmonic motion with
amplitude of M and period of 15 sec, then its vertical position is

   y(t) = y₀ + M sin(2π t/15) .

The vertical speed of the deck is   y'(t) = M (2π/15) cos(2π t/15)

and its vertical acceleration is y''(t) = - (2πM/15) (2π/15) sin(2π t/15)

      = - (4 π² M / 15²) sin(2π t/15)

      = - 0.1755 M sin(2π t/15) .

There's the important number ... the 0.1755 M.
That's the peak acceleration.
From here, the problem is a piece-o-cake.

The net vertical force on the intrepid sailor ... the guy standing on the
bathroom scale out on the deck of the ship that's "bobbing" on the
high seas ... is (the force of gravity) + (the force causing him to 'bob'
harmonically with peak acceleration of 0.1755 x amplitude).

At the instant of peak acceleration, the weighing machine thinks that
the load upon it is a mass of 65kg, when in reality it's only 60kg.
The weight of 60kg = 588 newtons.
The weight of 65kg = 637 newtons.
The scale has to push on him with an extra (637 - 588) = 49 newtons
in order to accelerate him faster than gravity.

Now I'm going to wave my hands in the air a bit:

Apparent weight = (apparent mass) x (real acceleration of gravity)

(Apparent mass) = (65/60) = 1.08333 x real mass.

Apparent 'gravity' = 1.08333 x real acceleration of gravity.

The increase ... the 0.08333 ... is the 'extra' acceleration that's due to
the bobbing of the deck.

0.08333 G = 0.1755 M

The 'M' is what we need to find.

Divide each side by 0.1755 : M = (0.08333 / 0.1755) G

'G' = 9.0 m/s²
   M = (0.08333 / 0.1755) (9.8) = 4.65 meters .

That result fills me with an overwhelming sense of no-confidence.
But I'm in my office, supposedly working, so I must leave it to others
to analyze my work and point out its many flaws.
In any case, my conscience is clear ... I do feel that I've put in a good
5-points-worth of work on this problem, even if the answer is wrong .

8 0

3 years ago

Which is an example of transforming potential energy to kinetic energy? Select two options.

Rasek [7]

Complete Question:

Which is an example of transforming potential energy to kinetic energy? Select two options.

changing thermal energy to electrical energy

changing chemical energy to thermal energy

changing nuclear energy to radiant energy

changing radiant energy to electrical energy

changing mechanical energy to chemical energy

Correct Answer:

The examples of transforming potential energy to kinetic energy are changing chemical energy to thermal energy and changing nuclear energy to radiant energy.

Explanation:

As stated by the conservation of energy law, any form of energy is usually transferred to another form. The basic kinds of energy is potential and kinetic energy. Potential energy is the energy stored for the objects at rest and kinetic energy is the energy utilized by the objects for motion.

So in the given options, chemical energy is the energy stored by the chemical bonds to make a stable compound and that energy is converted to thermal energy when the bonds get broken. So the stored energy or the energy required to keep the bonds intact is chemical energy and it is thus a form of potential energy.

And when these bonds get broken, the electrons use the thermal energy released by this breakage as their kinetic energy. So one form of transforming potential energy to kinetic energy is by changing chemical energy to thermal energy.

Similarly, the nuclear energy is exhibited by the elementary particles in an atom. So it is similar to potential energy and the radiant energy is released whenever there is an excitation. So the radiant energy will be similar to kinetic energy.

Thus, the changing of chemical energy to thermal energy and the changing of nuclear energy to radiant energy are the examples of transforming potential energy to kinetic energy.

5 0

3 years ago