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4 years ago

What gives the gem amethyst its purplish color

1 answer:

4 0

Amethyst is a crystalline quartz, its colours range from light to dark purple. The purplish colour of amethyst is due to high energy radiations, such as gamma rays, from radioactive sources, the presence of trace elements and the presence of iron found in its crystal lattice. The colour cetre created by Fe4+ is a principal contributor to the colouring of amethyst.

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FIGURE 1 shows part of a mass spectrometer. The whole arrangement is in a vacuum. Negative ions of mass 2.84 x 10-20 kg and char

yuradex [85]

Yes, the ions can exit slit P without being deflected, if the electric field strength is 170.6 N/C

Explanation:

When the ions are inside the container, they are subjected to two forces, with directions opposite to each other:

The force due to the electric field, whose magnitude is $F_E=qE$ , where q is the charge of the ion and E is the strength of the electric field
The force due to the magnetic field, whose magnitude is $F_B=qvB$ , where v is the speed of the ions and B is the strength of the magnetic field

The ions will move straight and undeflected if the two forces are equal and opposite. By using Fleming Left Hand rule, we notice that the magnetic force on the (negative) ions point upward: this means that the electric field must be also upward (so that the electric force on the ions is downward). Then, the two forces are balanced if

$F_E = F_B$

which translates into

$qE=qvB\\\rightarrow v = \frac{E}{B}$

Therefore, if the speed of the ions is equal to this ratio, the ions will go undeflected.

We can even calculate the value of E at which this occurs. In fact, we know that the ions are earlier accelerated by a potential difference $V=-3000 V$ , so we have that their kinetic energy is given by the change in electric potential energy:

$qV=\frac{1}{2}mv^2$

where

$q=-2.0\cdot 10^{-19}C\\m=2.84\cdot 10^{-20}kg$

Solving for v, the speed,

$v=\sqrt{\frac{2qV}{m}}=\sqrt{\frac{2(-2.0\cdot 10^{-19})(-3000)}{2.84\cdot 10^{-20}}}=205.6 m/s$

And since the magnetic field strength is

B = 0.83 T

The strength of the electric field must be

$E=vB=(205.6 m/s)(0.83 T)=170.6 N/C$

Learn more about electric and magnetic fields:

brainly.com/question/8960054

brainly.com/question/4273177

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brainly.com/question/4240735

#LearnwithBrainly

7 0

3 years ago

A projectile is launched at an angle of 36.7 degrees above the horizontal with an initial speed of 175 m/s and lands at the same

Softa [21]

Answer:

a) The maximum height reached by the projectile is 558 m.

b) The projectile was 21.3 s in the air.

Explanation:

The position and velocity of the projectile at any time "t" is given by the following vectors:

r = (x0 + v0 · t · cos α, y0 + v0 · t · sin α + 1/2 · g · t²)

v = (v0 · cos α, v0 · sin α + g · t)

Where:

r = position vector at time "t"

x0 = initial horizontal position

v0 = initial velocity

t = time

α = launching angle

y0 = initial vertical position

g = acceleration due to gravity (-9.80 m/s² considering the upward direction as positive).

v = velocity vector at time t

a) Notice in the figure that at maximum height the velocity vector is horizontal. That means that the y-component of the velocity (vy) at that time is 0. Using this, we can find the time at which the projectile is at maximum height:

vy = v0 · sin α + g · t

0 = 175 m/s · sin 36.7° - 9.80 m/s² · t

- 175 m/s · sin 36.7° / - 9.80 m/s² = t

t = 10.7 s

Now, we have to find the magnitude of the y-component of the vector position at that time to obtain the maximum height (In the figure, the vector position at t = 10.7 s is r1 and its y-component is r1y).

Notice in the figure that the frame of reference is located at the launching point, so that y0 = 0.

y = y0 + v0 · t · sin α + 1/2 · g · t²

y = 175 m/s · 10.7 s · sin 36.7° - 1/2 · 9.8 m/s² · (10.7 s)²

y = 558 m

The maximum height reached by the projectile is 558 m

b) Since the motion of the projectile is parabolic and the acceleration is the same during all the trajectory, the time of flight will be twice the time it takes the projectile to reach the maximum height. Then, the time of flight of the projectile will be (2 · 10.7 s) 21.4 s. However, let´s calculate it using the equation for the position of the projectile.

We know that at final time the y-component of the vector position (r final in the figure) is 0 (because the vector is horizontal, see figure). Then:

y = y0 + v0 · t · sin α + 1/2 · g · t²

0 = 175 m/s · t · sin 36.7° - 1/2 · 9.8 m/s² · t²

0 = t (175 m/s · sin 36.7 - 1/2 · 9.8 m/s² · t)

0 = 175 m/s · sin 36.7 - 1/2 · 9.8 m/s² · t

- 175 m/s · sin 36.7 / -(1/2 · 9.8 m/s²) = t

t = 21.3 s

The projectile was 21.3 s in the air.

7 0

3 years ago

What causes diffferent air density?

ololo11 [35]

Answer:

The temperature and gravity both affects the density

5 0

3 years ago

A plane traveled for 3 hours at a velocity of 1200 km/hr North. What is the distance traveled?

Daniel [21]

Answer:

the answer is 3600 kilometers

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3 years ago

What TWO things happen to solar radiation that reaches earth?

-Dominant- [34]

The energy of the reflected radiation goes back into outer space. The other 70% of solar radiation that gets to Earth is absorbed. Most of the energy is absorbed by oceans, landforms, and living things.

4 0

3 years ago

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