A car traveling at 22.4 m/s skids to a stop in 2.55s determine the skidding distance of the car ?

The findings of Henri Becquerel and the Curies helped to discredit what notion held for a very long time? That matter is indivis

Anon25 [30]

Answer:

Matter is radioactive and decays over time.

Explanation:

Becquerel and the Curies discovered the radioactivity.

The Curies died because they did a lot of experiments using Radio and other elements.

The other alternatives are concepts that are known for a long time.

5 0

3 years ago

PLEASE HELP!! What needs to happen for solid water to change to liquid water?

Vlad [161]

Answer:

The answer is D.

Explanation:

I took the test.

7 0

2 years ago

How should we take good care of your hygiene when playing basketball and volleyball.

kolezko [41]

Answer taking care of the body, skin, hair, eyes, teeth, legs, as well as our clothes. Physical exercises and supporting activities, sleep and rest and nutritious food come under personal hygiene. drink enough of water of your bodyweight and stretch.

Explanation:

5 0

3 years ago

Arsenic diffusion in Si: Arsenic is diffused into a thick slice of silicon with no previous arsenic in it at 1100ºC. If the surf

Rainbow [258]

Answer:

Diffusion time is 7.42 h

Solution:

As per the question:

Temperature, T = $1100^{\circ}C$

Surface concentration of arsenic, $C_{S} = 5.0\times 10^{18}\ atoms/cm^{3}$

Surface concentration below Silicon surface, $C_{x} = 1.5\times 10^{16}\ atoms/cm^{3}$

D = $3.0\times 10^{- 14}\ cm^{2}/s$

x = $1.2\mu m = 1.2\times 10^{- 4}\ cm$

Initial concentration at t = 0, $C_{o} = 0$

Now, by using Flick's second eqn:

$\frac{C_{S} - C_{x}}{C_{x} - C_{o}} = erf(\frac{x}{\sqrt{Dt}})$

Thus by putting appropriate values:

$\frac{5.0\times 10^{18} - 1.5\times 10^{16}}{5.0\times 10^{18}} = erf(\frac{1.2\times 10^{- 4}}{2\sqrt{3.0\times 10^{- 14}t}})$

$0.997 = erf(\frac{364.4}{\sqrt{t}})$ (1)

Now,

$erf(z) = 0.997$

Now, from error function values tabulation:

For z = 2.0, erf(z) = 0.998

For z = 2.2, erf(z) = 0.995

Now,

With the help of linear interpolation method:

$\frac{z - 2}{2.2 - 2.0} = \frac{0.997 - 0.995}{0.998 - 0.995}$

z = 2.12

Now, using eqn (1) and above value:

$\frac{364.4}{\sqrt{t}} = 2.12$

$t = (\frac{364.4}{2.12})^{2}$ = 26700 s

t = $\frac{26700}{3600} = 7.42\ h$

7 0

3 years ago

"Two electrons in an atom are separated by 1.4 × 10−10 m, the typical size of an atom. What is the force between them? The Coulo

Rudiy27

Answer:

$F\approx 1.17551\times 10^{-8} N$

Explanation:

In order to find the force between the two electrons, we need to use Coulomb's law. In its scalar form, the law is given by:

$F=k_c \frac{q_1*q_2}{r^2}$

Where:

$k_c=Coulomb\hspace{3}constant\approx 9\times10^{9} \frac{Nm^2}{C^2} \\q_1\hspace{3}and\hspace{3}q_2=Magnitudes\hspace{3}of\hspace{3}the\hspace{3}charges\\r=Distance\hspace{3}between\hspace{3}the\hspace{3}charges$

The electric charge of an electron is a known constant given by:

$q_e \approx -1.6 \times 10^{-19} C$

So:

$q_1=q_2=q_e \approx -1.6 \times 10^{-19} C$

Therefore, replacing the data provided in the Coulomb's law equation:

$F=(9\times 10^{9})\frac{(-1.6\times 10^{-19})*(-1.6\times 10^{-19})}{(1.4\times 10^{-10})^2} =1.175510204\times10^{-8} \approx 1.17551\times10^{-8}N$

8 0

3 years ago