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3 years ago

Tooth fillings are often made of gold or porcelain because these materials are ______.

Physics

2 answers:

garri49 [273]3 years ago

4 0

Tooth fillings are often made of gold or porcelain because these materials are nonreactive.

b. nonreactive.

damaskus [11]3 years ago

3 0

Tooth fillings are often made of gold or porcelain because these materials are:

b. nonreactive

That means that they don't corrode or rust and they are resistible to staining.Their thermal conductibility is low.

Explanation:

Porcelain-fused-to-metal crowns. PFM crowns are an approximately esthetic improvement that has been in use for more than 40 years. In one way, they blend the best of both worlds, a crown made of “refined or noble” metal (gold or platinum), which is strong, fits correctly and is bonded/bonded to the tooth.

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I need to choose a theme for my physics assignment My experiment is finding g

Kobotan [32]

<h3>Question:</h3>

How to find g (acceleration due to gravity)

<h3>Solution:</h3>

We know,

Acceleration due to gravity (g)

$= \frac{GM}{ {R}^{2} }$

where, G = Gravitational constant

$= 6.67 \times {10}^{11} N {m}^{2}/k {g}^{2} \\$

M = Mass of the earth

$= 6 \times {10}^{24} \: kg$

R = Radius of the earth

$= 6.4 \times {10}^{6} m$

Putting these values of G, M and R in the above formula, we get

$g \: = \: \frac{6.67 \times {10}^{11} N {m}^{2}/k {g}^{2} \times \: 6 \times {10}^{24} \: kg }{(6.4 \times {10}^{6}m {)}^{2} } \\ = 9.8m/ {s}^{2}$

So, the value of acceleration due to gravity is

$9.8m/s ^{2}$

Hope it helps.

Do comment if you have any query.

5 0

2 years ago

Which of the following is constant during uniform circular motion?

tatuchka [14]

An object undergoing <span>uniform circular motion </span>is moving with a constant speed. Nonetheless, it is accelerating due to its change in direction. So I'm thinking velocity

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2 years ago

Ask Your Teacher In the air over a particular region at an altitude of 500 m above the ground, the electric field is 120 N/C dir

strojnjashka [21]

Answer:

$1.475\times 10^{-13}\ C/m^3$

Explanation:

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A = Area

h = Altitude = 600 m

Electric flux through the top would be

$-110A$ (negative as the electric field is going into the volume)

At the bottom

$120A$

Total flux through the volume

$\phi=120-110\\\Rightarrow \phi=10A$

Electric flux is given by

$\phi=\dfrac{q}{\epsilon_0}\\\Rightarrow q=\phi\epsilon_0\\\Rightarrow q=10A\epsilon_0$

Charge per volume is given by

$\rho=\dfrac{q}{v}\\\Rightarrow \rho=\dfrac{10A\epsilon_0}{Ah}\\\Rightarrow \rho=dfrac{10\epsilon_0}{h}\\\Rightarrow \rho=\dfrac{10\times 8.85\times 10^{-12}}{600}\\\Rightarrow \rho=1.475\times 10^{-13}\ C/m^3$

The volume charge density is $1.475\times 10^{-13}\ C/m^3$

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2 years ago

An airplane with a mass of 5,000 kg needs to accelerate 5 m/s2 to take off before it reaches the end of the runway. How much for

Anastasy [175]

Answer:

Explanation:

The force acting on an object given it's mass and acceleration can be found by using the formula

force = mass × acceleration

From the question we have

force = 5000 × 5

We have the final answer as

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2 years ago

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yulyashka [42]

Answer:

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Explanation:

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2 years ago

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