Answer:
The process of evaporative cooling helps the body is explained below in complete details.
Explanation:
Your body performs the application of the evaporative process when secreting. Sweat, which contains 90 percent water, commences evaporating. ... This appears in a cooling impression (described as evaporative cooling) that serves to sustain body temperature and cools the body down when it becomes too hot.
Picking up a box, pushing a box along the ground, and pulling a box along the ground (B, C, and D) definitely involve work being done.
If a person CARRIES a box from one place to another, AND keeps it at the same height during the entire carry, then no work is done. ( A )
Answer:
a. 9.52 cm b. 4.34 × 10⁶ m/s
Explanation:
a. The horizontal distance traveled by the electron when it hits the plate.
The electric force F on the electron due to the electric field E of mass, m is
F = -eE = ma
a = -eE/m where a = acceleration of electron
The vertical distance moved by the electron is given by
Δy = ut +1/2at²
u = initial vertical velocity = 0. and take the top plate as y = 0 and bottom plate as y
So,
0 - y = 0 × t + 1/2at²
-y = 1/2at²
substituting a = -eE/m
-y = 1/2(-eE/m)t²
y = eEt²/2m
making t subject of the formula,
t = √(2ym/eE) where t is the time it takes to reach the bottom plate.
Since E = 4.0 × 10² N/C, y = distance between plates = 2.0 cm = 0.02 m, m = 9.109 × 10⁻³¹kg and e = 1.602 × 10⁻¹⁹ C
t = √[(2 × 0.02 m × 9.109 × 10⁻³¹kg)/(1.602 × 10⁻¹⁹ C × 4.0 × 10² N/C)]
t = √[(0.36436 × 10⁻³¹kgm)/(6.408 × 10⁻¹⁷ N)]
t = √[(0.0569 × 10⁻¹⁴kgm/N)t
t = 0.238 × 10⁻⁷ s
t = 23.8 × 10⁻⁹ s
t = 23.8 ns
The horizontal distance moved when it hits the plates x = vt where v = initial horizontal velocity = 4.0 × 10⁶ m/s
x = 4.0 × 10⁶ m/s × 23.8 × 10⁻⁹ s
= 0.0952 m
= 9.52 cm
b. The velocity of the electron as it strikes the plate.
To find the velocity of the electron as it strikes the plates, we calculate its final vertical velocity V as it strikes the plate. This is gotten from
v' = u + at since u = 0,
v' = at
= -eEt/m
= -(1.602 × 10⁻¹⁹ C × 4.0 × 10² N/C × 0.238 × 10⁻⁷ s)/9.109 × 10⁻³¹kg
= -1.525 × 10⁻²⁴ Ns/9.109 × 10⁻³¹kg
= -0.167 × 10⁷ m/s
= -1.67 × 10⁶ m/s
So, the resultant velocity as it strikes the plate v = √(v'² + v²)
= √((-1.67 × 10⁶ m/s)² + (4 × 10⁶ m/s)²)
= √(2.7889 + 16) × 10⁶ m/s
= √18.7889 × 10⁶ m/s
= 4.335 × 10⁶ m/s
≅ 4.34 × 10⁶ m/s
With almost all substances . . .
-- when you cool them, their electrical resistance decreases.
-- If you make them even colder, their resistance decreases more.
-- If you make them even colder, their resistance decreases more.
-- If you make them even colder, their resistance decreases more.
-- If you keep making them colder, their resistance keeps decreasing,
but it never completely disappears, no matter how cold you make them.
But with a few surprising substances, called 'superconductors' . . .
-- when you cool them, their electrical resistance decreases.
-- If you make them even colder, their resistance decreases more.
-- If you make them even colder, their resistance decreases more.
-- If you make them even colder, their resistance decreases more.
-- If you keep making them colder, then suddenly, at some magic
temperature, their resistance COMPLETELY disappears. It doesn't
just become small, and it doesn't just become too small to measure.
It becomes literally totally and absolutely ZERO.
If you start a current flowing in a superconducting wire, for example,
you can connect the ends of the wire together, and the current keeps
flowing around and around in it, for months or years. As long as you
keep the loop cold enough, the current never decreases, because
the superconducting wire has totally ZERO resistance.
Did somebody say "What's this good for ? What can you do with it ?"
1). Every CT-scan machine and every MRI machine needs many
powerful magnets to do its thing. They are all electromagnets, with
coils of superconducting wire, enclosed in containers full of liquid helium.
Yes, it's complicated and expensive. But it turns out to be simpler and
cheaper than using regular electromagnets, with coils of regular plain
old copper wire, AND the big power supplies that would be needed
to keep them going.
2). Resistance in wire means that when current flows through it,
energy is lost. The long cables from the power-generating station
to your house have resistance, so energy is lost on the way from the
generating station to your house. That lost energy is energy that the
electric company can't sell, because they can't deliver it to customers.
There are plans to build superconducting cables to carry electric power
from the producers to the customers. The cables will be hollow pipes,
with liquid helium or liquid hydrogen inside to keep them cold, and
something on the outside to insulate them from the warmth outside.
Yes, they'll be complicated and expensive. But they'll have ZERO
resistance, so NO energy will be lost on its way from the generating
stations to the customers. The power companies think they can
build superconducting 'transmission lines' that will cost less than
the energy that's being lost now, with regular cables.
Boruto because he got naruto
