8. Volcanoes that are mostly made up of pyroclastic material are called?

In an early attempt to understand atomic structure, Niels Bohr modeled the hydrogen atom as an electron in uniform circular moti

AleksandrR [38]

Answer:

The answer is below

Explanation:

Using Coulomb's law of electric field which is:

$F=k\frac{q_1q_1}{r^2}\\\\ k =constant=9*10^9\ Nm^2/C^2,q_1=q_2=1.6*10^{-19}C,r=5.29*10^{-11}m\\\\Substituting\ gives:\\\\F=9*10^9*\frac{(1.6*10^{-19})*(1.6*10^{-19})}{(5.29*10^{-11})^2} =8.22*10^{-8}N\\\\Both\ centripetal\ force\ is\ given\ by:\\\\F=m\frac{v^2}{r} \\\\m = mass\ of \ electron=9.11*10^{-31}g,v=speed\ of\ electron\\\\F=m\frac{v^2}{r} \\\\v=\sqrt{\frac{F*r}{m} } \\\\subsituting:\\\\v=\sqrt{\frac{8.22*10^{-8}*5.29*10^{-11}}{9.11*10^{-31}} } \\\\v=2.18*10^6\ m/s\\\\$

$But\ \omega=\frac{v}{r}=\frac{2.18*10^6}{5.29*10^{-11}} =4.13*10^{17}\\\\\omega=2\pi f; f=frequency\\\\f=\frac{\omega}{2\pi} =\frac{4.13*10^{17}}{2\pi} \\\\f=6.57*10^{15}\ Hz$

6 0

3 years ago

What is the distance between a 2000 kg truck and a 3000 kg truck if the gravitational force between them is 0.00006 N?

Andrew [12]

Answer:

A. 2.58m

Explanation:

Using the formula;

F = GMm/r²

M and m are the masses

G is the gravitational constant

r is the distance between the masses

Substitute

0.00006 = 6.67*10^-11(2000)(3000)/r²

0.00006r² = 6.67*10^-11*6000000

0.00006r² = 40.02*10^-5

0.00006r² = 0.0004

r² = 0.0004/0.00006

r² = 6.66

r = 2.58m

Hence the distance between them is 2.58m

4 0

3 years ago

Which is not a physical property?

mihalych1998 [28]

The correct answer to the question is D). Ability to combine with oxygen.

EXPLANATION:

Before going to answer this question, first we have to understand physical and chemical change.

The change or reaction is said to be physical if there will be no change in the chemical configuration of the substance. The property corresponding to this change is called physical property which won't change the configuration of the substance. It is measurable and simply denotes the physical states of a system.

A chemical change is a change in which a new substance is formed due to the chemical reaction. Here, both the reactants and products have different chemical configuration. The property corresponding to it is called chemical property.

As per our questions, hardness, boiling and ability to conduct electricity are the physical properties of a substance.

The ability to combine with oxygen is not a physical property. It is so because it will result into the formation of a new compound.

Hence, the correct answer to the question is the ability to combine with oxygen.

3 0

4 years ago

A capacitor has a charge of 4.6 Î¼C. An E-field of 1.8 kV/mm is desired between the plates. There's no dielectric. What must be

Scrat [10]

Answer:

$A = 0.2875 m^2$

Explanation:

As we know that

$Q = 4.6 \mu C$

E = 1.8 kV/mm

now we know that electric field between the plated of capacitor is given as

$E = \frac{\sigma}{\epsilon_0}$

now we will have

$1.8 \times 10^6 = \frac{\sigma}{\epsilon_0}$

$\sigma = (1.8 \times 10^6)(8.85 \times 10^{-12})$

$\sigma = 1.6 \times 10^{-5} C/m^2$

now we have

$\sigma = \frac{Q}{A}$

now we have area of the plates of capacitor

$A = \frac{Q}{\sigma}$

$A = \frac{4.6 \times 10^{-6}}{1.6 \times 10^{-5}}$

$A = 0.2875 m^2$

5 0

3 years ago

The name (blank) means "all land"

mina [271]

I would say the answer is Pangaea. I got this answer but google searching "all land" means what... and the 3rd or 4th one down it says Answers.com
But i worn you answers.com is a very slow sight...
Hope it helps
and please mark me as brainiest

4 0

4 years ago