Answer:
Beryllium
Beryllium is an alkaline metallic element that is highly toxic. It is known for its sugary sweet taste and some of its common uses are in X-rays and fluorescent lights.
Beryllium : A very thorough and technical site about this mineral.
Chromite
Chromite is the ore of chromium and is a very hard metal, and diamond is the only thing harder. This hardness is what allows a chrome finish to take a high polish.
Chromite : This site talks about its history and characteristics.
Cobalt
Cobalt is famous for the incredible blue color it imparts to glass and pigment. It has been found in meteorites and is used in invisible ink. It is a brittle metal and resembles iron.
Cobalt : This site has photos, video, charts and physical and atomic descriptions.
Columbite-tantalite
Columbite-tantalite group is a mineral used widely in technology. Electronics, automotive systems and health products like the pacemaker need this mineral to operate. It is mined in Africa and has earned the name of Coltan over the last few years.
Columbite-tantalite : Information about its role in the world under the name 'Coltan'.
Copper
Copper is a common metal throughout the world. It is used for currency, jewelry, plumbing and to conduct electricity. It is a soft, orange-red metal.
Copper : This site talks about its properties, uses and makeup.
Explanation:
Hope that helps :)
Answer:
The answer is going to be C.
Explanation:
Trust me. Im an expert in physics
Answer:
There's a decrease in width of 2.18 × 10^(-6) m
Explanation:
We are given;
Shear Modulus;E = 207 GPa = 207 × 10^(9) N/m²
Force;F = 60000 N.
Poisson’s ratio; υ =0.30
We are told width is 20 mm and thickness 40 mm.
Thus;
Area = 20 × 10^(-3) × 40 × 10^(-3)
Area = 8 × 10^(-4) m²
Now formula for shear modulus is;
E = σ/ε_z
Where σ is stress given by the formula Force(F)/Area(A)
While ε_z is longitudinal strain.
Thus;
E = (F/A)/ε_z
ε_z = (F/A)/E
ε_z = (60,000/(8 × 10^(-4)))/(207 × 10^(9))
ε_z = 3.62 × 10^(-4)
Now, formula for lateral strain is;
ε_x = - υ × ε_z
ε_x = -0.3 × 3.62 × 10^(-4)
ε_x = -1.09 × 10^(-4)
Now, change in width is given by;
Δw = w_o × ε_x
Where w_o is initial width = 20 × 10^(-3) m
So; Δw = 20 × 10^(-3) × -1.09 × 10^(-4)
Δw = -2.18 × 10^(-6) m
Negative means the width decreased.
So there's a decrease in width of 2.18 × 10^(-6) m
Answer:
D) 763 nm
Explanation:
Calculation for the wavelength of light
Using this formula
Wavelength of light=Delta Y*Distance / Length
Where,
Delta Y represent the 2nd order bright fringe
Length represent the distance between both the slits and the screen
Distance represent the Distance between the slits
Let note that cm to m = (4.2) x 10^-2 and mm to m= ( 0.0400x 10^-3)
Now Let plug in the formula
Wavelength of light=[(4.2 x 10^-2m)(0.0400 x 10^-3m) / 2(1.1m)]*10^-7 meters
Wavelength of light=[(0.042m) (0.0004m)/2.2m]*10^-7 meters
Wavelength of light =(0.0000168m/2.2m)*10^-7 meters
Wavelength of light =7.63 *10^-7 meters
Wavelength of light =763 nm
Therefore the Wavelength of light will be 763 nm
We use the Rydberg Equation for this which is expressed as:
<span>1/ lambda = R [ 1/(n2)^2 - 1/(n1)^2]
</span>
where lambda is the wavelength, where n represents the final and initial states. Brackett series means that the initial orbit that electron was there is 4 and R is equal to 1.0979x10^7m<span>. Thus,
</span>
1/ lambda = R [ 1/(n2)^2 - 1/(n1)^2]
1/1.0979x10^7m = 1.0979x10^7m [ 1/(n2)^2 - 1/(4)^2]
Solving for n2, we obtain n=1.
