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bearhunter [10]
2 years ago
11

If a young protostar with a disk is rotating and shrinking. how much faster is it rotating after its size has decreased by a fac

tor of 4? (enter an integer, as in it will be rotating ________ times faster). (3 pts)
Physics
1 answer:
maks197457 [2]2 years ago
5 0
In this system we have the conservation of angular momentum: L₁ = L₂
We can write L = m·r²·ω

Therefore, we will have:
m₁ · r₁² · ω₁ = m₂ · r₂² · ω₂

The mass stays constant, therefore it cancels out, and we can solve for ω<span>₂:
</span>ω₂ =  (r₁/ r₂)² · ω<span>₁
     
Since we know that r</span>₁ = 4r<span>₂, we get:
</span>ω₂ =  (4)² · ω<span>₁
     = 16 </span>· ω<span>₁

Hence, the protostar will be rotating 16 </span><span>times faster.</span>
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Which field in an 802.11a plcp frame are used to initialize part of the transmitter and receiver circuits?
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What Class Is this for?
4 0
2 years ago
Titanium metal requires a photon with a minimum energy of 6.94×10−19J to emit electrons. If titanium is irradiated with light of
butalik [34]

Answer:

a) 1.59(10)^{-19} J

b) 2.34(10)^{12} electrons

Explanation:

The photoelectric effect consists of the emission of electrons (electric current) that occurs when light falls on a metal surface under certain conditions.  

If the light is a stream of photons and each of them has energy, this energy is able to pull an electron out of the crystalline lattice of the metal and communicate, in addition, a kinetic energy.  

<u>This is what Einstein proposed: </u>

Light behaves like a stream of particles called photons with an energy  E:

E=\frac{hc}{\lambda} (1)  

So, the energy E of the incident photon must be equal to the sum of the Work function \Phi of the metal and the kinetic energy K of the photoelectron:  

E=\Phi+K (2)  

Where \Phi=6.94(10)^{-19} J is the minimum amount of energy required to induce the photoemission of electrons from the surface of Titanium metal.

Knowing this, let's begin with the answers:

<h3 /><h3>a)  Maximum possible kinetic energy of the emitted electrons (K)</h3>

From (1) we can know the energy of one photon of 233 nm light:

E=\frac{hc}{\lambda}

Where:

h=6.63(10)^{-34}J.s is the Planck constant  

\lambda=233 (10)^{-9} m is the wavelength

c=3 (10)^{8} m/s is the speed of light

E=\frac{(6.63(10)^{-34}J.s)(3 (10)^{8} m/s)}{3 (10)^{8} m/s} (3)

E=8.53(10)^{-19} J (4) This is the energy of one 233 nm photon

Substituting (4) in (2):

8.53(10)^{-19} J=6.94(10)^{-19} J+K (5)  

Finding K:

K=1.59(10)^{-19} J (5)  This is the maximum possible kinetic energy of the emitted electrons

<h3>b) Maximum number of electrons that can be freed by a burst of light whose total energy is 2 \mu J=2(10)^{-6} J</h3>

Since one photon of 233 nm is able to free at most one electron from the Titanium metal, we can calculate the following relation:

\frac{E_{burst}}{E}

Where E_{burst}=2(10)^{-6} J is the energy of the burst of light

Hence:

\frac{E_{burst}}{E}=\frac{2(10)^{-6} J}{8.53(10)^{-19} J}=2.34(10)^{12} electrons This is the maximum number of electrons that can be freed by the burst of light.

4 0
2 years ago
Why do meteors in a meteor shower appear to come from just one point in the sky?
kolbaska11 [484]

Answer:

All the meteors in a meteor shower typically come from the same comet, which is in a periodic orbit around the Sun. The dust from the comet follows the path of the parent body and as Earth intersects the debris along the comet's orbit, it plows into this material. Since the dust particles are all moving together in space before they encounter Earth, if you trace back the streak of each meteor, its path will appear to diverge from one place in the sky.

4 0
2 years ago
A couch is pushed with a horizontal force of 80 N and moves the couch a
Lapatulllka [165]

Answer:

400 J

Explanation:

Work = force × distance

W = (80 N) (5 m)

W = 400 J

5 0
2 years ago
Read 2 more answers
If in a vernier callipers 10 VSD coincides with 8 MSD then the least count of varnier calliper is
ratelena [41]

Answer:0.2mm

Explanation:

The length of one VSD=8/10=0.8mm

The least count of the instrument is the difference between the length of one MSD and length of one VSD

The length of inebriated MSD=1mm

Therefore,

The least count=1-0.8=0.2mm

3 0
2 years ago
Read 2 more answers
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