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4 years ago

A. What is the basic building block of matter?

Physics

2 answers:

Makovka662 [10]4 years ago

5 0

a) Everything's made of atoms! Despite the fact that they still can be split to nucleons and quarks...

b) From lightest to the heaviest: electrons (charge -1), protons (+1), neutrons (0 charge).

c) Atoms are electrically neutral and ions doesn't

d) Negative ion has more negative charges - electrons, so they are in majority.

e) In Thomson's model of atom charges were uniformly spread in the atom's volume. He thought that this model is enough to describe atoms' neutrality.

Nikitich [7]4 years ago

4 0

Answer:

a. atoms are the basic building blocks of matter. The atom is made of electrons and protons. It contains the chemical identity of an element.

b. Three types of particles that make up an atom are:

electrons - these are negatively charged particles and lightest constituents of an atom.

protons are positively charges and is 1873 times heavier than an electron.

Neutrons are neutral particles having mass equivalent to mass of proton.

Protons and neutrons exist in the center of an atom in nucleus and electrons revolve around the nucleus.

c. An atom is a neutral entity where as an ion is charged. An ion has excess of electrons or lacks electrons due to which it has negative or positive charge. An atom has an equal number of electrons and protons.

d. In a negative ion, the number electrons is greater than number of protons. The atom when gains electrons becomes negative ion.

e. John Dalton proposed Solid sphere model in which tiny invisible particles constitute matter. These invisible particles are atoms and these are indivisible.

You might be interested in

Racing greyhounds are capable of rounding corners at very high speeds. A typical greyhound track has turns that are 45 m diamete

Readme [11.4K]

Answer:

In m/s^2:

a=11.3778 m/s^2

In units of g:

a=1.161 g

Explanation:

Since the racing greyhounds are capable of rounding corners at very high speed so we are going use the following formula of acceleration for circular paths.

$a=\frac{v^2}{r}$

where:

v is the speed

r is the radius

Now,

$a=\frac{16^2}{45/2}\\ a=11.3778 m/s^2$

In g units:

$a=\frac{11.3778\ g}{9.8}\\ a=1.161\ g$

7 0

3 years ago

David is investigating the properties of soil using the sample shown.

xenn [34]

Although the sample is not shown in this question, we can conclude that it would be reasonably easy for David to provide evidence of the color, consistency, temperature, and texture of the soil.

<h3 />

<h3>What are these properties an example of?</h3>

These are all examples of the physical properties of a sample. Since we cannot see the sample that David is using, it would be safest to assume that he would have no trouble providing evidence as to the physical properties of the soil, the:

Color
Consistency
Temperature
Texture

are all examples of this.

Therefore, we can confirm that David can provide evidence of the color, consistency, temperature, and texture of the soil.

To learn more about physical properties visit:

brainly.com/question/24632287?referrer=searchResults

7 0

3 years ago

Ow much charge flows from a 12.0 v battery when it is connected across a completely discharged 18.0 μf capacitor

Trava [24]

The equation Q=CV (Charge = product of Capacitance and potential difference) tells us that the maximum charge that can be stored on a capacitor is equal to the product of it's capacitance and the potential difference across it. In this case the potential difference across the capacitor will be 12.0V (assuming circuit resistance is negligable) and it has a capacitance of 18.0μf or 18.0x10^-6f, therefore charge equals (18.0x10^-6)x12=2.16x10^-4C (Coulombs).

5 0

3 years ago

You need to build a prototype with machined parts that withstand a saline corrosive environment and temperatures above 200 degre

kondor19780726 [428]

Answer:

Stainless steel

Explanation:

I will try to order the solutions from the least correct to the most correct.

Since a temperature greater than 200 ° F is required, that is to say approximately 93 ° c, <em>Polycaprolactone</em> is the least indicated. Its melting point is approximately 60 ° C, so it would not serve the required application.

On the other hand we have<em> Untreated aluminum</em>, which although it has a melting point higher than the required one, without a zinc and magnesium treatment it will easily oxidize in a salty environment, so it cannot be used in this choice either.

We have to compare the two steels.

The<em> Mild Steel </em>has a better corrosion resistance than the previous ones, but in a long-term cycle it will end up full of corrosion and therefore its properties will be highly affected.

Finally, we have <em>stainless steel</em>, which, as the name implies, contains in some of its variations chromium, zinc or magnesium in its alloys, which makes it highly resistant to corrosion.

In addition its melting point is above 1500 ° c.

The best choice is stainless steel.

5 0

3 years ago

The kinetic friction force between a 60.0-kg object and a horizontal surface is 50.0 N. If the initial speed of the object is 25

Vikki [24]

Answer:

375 m.

Explanation:

From the question,

Work done by the frictional force = Kinetic energy of the object

F×d = 1/2m(v²-u²)..................... Equation 1

Where F = Force of friction, d = distance it slide before coming to rest, m = mass of the object, u = initial speed of the object, v = final speed of the object.

Make d the subject of the equation.

d = 1/2m(v²-u²)/F.................. Equation 2

Given: m = 60.0 kg, v = 0 m/s(coming to rest), u = 25 m/s, F = -50 N.

Note: If is negative because it tends to oppose the motion of the object.

Substitute into equation 2

d = 1/2(60)(0²-25²)/-50

d = 30(-625)/-50

d = -18750/-50

d = 375 m.

Hence the it will slide before coming to rest = 375 m

6 0

3 years ago