Why are models of atoms and molecules useful explain

Answers

Answer 1

Answer:

The models are larger versions of atoms/molecules. It is a visualization so we can understand the super small particles.

Explanation:

Atoms and molecules are very, very, small. They average 100 picometers across.

They definitely cannot be seen with the naked human eye. We can only see them with special microscopes (electron, optical, etc).  that magnify hundreds of thousands of times.

So, we use models of atoms and molecules. It allows us to study, visualize, understand,  and "see" the particles on a much larger scale.


Related Questions


Surface water is replaced by the blank cycle.

Answers

Answer: Surface water is replaced by the water cycle.

Explanation: The water cycle is a cycle that describes the movement of water.

Answer:

it is water cycle when it's one of the process occurs and process is precipation this replaces surface water

Block X and block Y travel toward each other along a horizontal surface with block X traveling in the positive direction. Block X has a mass of 4kg and a speed of 2ms. Block Y has a mass of 1kg and a speed of 1 ms. A completely inelastic collision occurs in which momentum is conserved. What is the approximate speed of block X after the collision

Answers

Answer:

  v = 1.4 m / s

Explanation:

To solve this problem we use the law of conservation of momentum, for this we define a system formed by the two blocks in such a way that the force during the collision have been internal

initial instant. Just before the crash

           p₀ = M v₁ - m v₂

final instant. Right after the crash

          p_f = (M + m) v

the moment is preserved

          p₀ = p_f

          M v₁ - m v₂ = (M + m) v

           v = [tex]\frac{1}{M+m}[/tex]  (M v₁ - mv₂)

let's calculate

           v = [tex]\frac{1}{4+1}[/tex]  (4 2 - 1 1)

           v = 1.4 m / s

in the same direction as the largest block (M)

The approximate speed of block X after the collision is 1.4 m/s.

Given information:

Block X and block Y travel toward each other along a horizontal surface with block X traveling in the positive direction.

Block X has a mass of [tex]m_1=[/tex] 4 kg and a speed of [tex]u_1=[/tex] 2 m/s.

Block Y has a mass of [tex]m_2=[/tex] 1 kg and a speed of [tex]u_2=[/tex] -1 m/s.

The collision between them is perfectly inelastic. So, the final velocity of both the objects will be the same.

The momentum of the system will be conserved. Let v be the final velocity of both the blocks.

The final velocity v can be calculated as,

[tex]m_1u_1+m_2u_2=(m_1+m_2)v\\4\times 2-1\times1=(4+1)v\\5v=7\\v=1.4\rm\;m/s[/tex]

Therefore, the approximate speed of block X after the collision is 1.4 m/s.

For more details about collision, refer to the link:

https://brainly.com/question/12941951

What is the torque on a bolt applied with a wrench that has a
lever arm of 30 cm with a force of 30 N?​

Answers

Answer:

9 Nm

Explanation:

The formula for torque is;

τ = lever arm * force applied

τ = 30/100 * 30

τ = 9 Nm

The torque on a bolt will be "9 Nm".

Given values are:

Force applied,

30 N

Lever arm,

30 cm

As we know the formula,

→ [tex]\tau = Lever \ arm\times force \ applied[/tex]

By substituting the values, we get

→    [tex]= \frac{30}{100}\times 30[/tex]

→    [tex]= 9 \ Nm[/tex]

Thus the above response is correct.    

Learn more:

https://brainly.com/question/20372081

Of the charge Q initially on a tiny sphere, a portion q is to be transferred to a second, nearby sphere. Both spheres can be treated as particles. For what value of q/Q>0.5 will the electrostatic force between the two parts have 1/3 of the maximum possible value?

Answers

Answer:

Explanation:

Maximum value of force will be possible when both the sphere will have same charge . In that case charge on each sphere = Q / 2 =.5Q

F( max ) = k .5Q x .5Q / R²

=.25kQ² /R²

For the second case

F = k q ( Q-q)/  R²

F = .25kQ² /3R²

.25kQ² /3R² =  k q ( Q-q)/  R²

.25 Q² = 3qQ - 3q²

3q² - 3qQ + .25 Q² = 0

q =

In which part of a lab report would be the following sentence most likely occur? “Since the data showed that the

Answers

We’re are the answer choices at?

Answer:

most likely be included in the analysis section of a lab report

Explanation:

In the picture shown below A represents a characteristic of only geocentric model, B represents a characteristic common to both geocentric and heliocentric models, C represents a characteristic of only heliocentric model, and D represents a characteristic which the geocentric and heliocentric models do not have.
Under which label will the characteristic, "The sun and planets revolve around a central moon in the solar system" fall?
A
B
C
D

Answers

Sorry I wish I can help but there is no picture

A frictionless cart of mass M is attached to a spring with spring constant k. When the cart is displaced 6 cm from its rest position and released, it oscillates with a period of 2 seconds.Four English majors are discussing what would happen to the period of oscillation if the cart was displaced 12 cm from its rest position instead of 6 cm and again released.With which, if any, of these students do you agree?

Answers

Answer:

Time period of horizontal Oscillation  = T = 2[tex]\pi[/tex][tex]\sqrt{\frac{m}{k} }[/tex]

As you can see, from the equation, Period of oscillation depends upon the mass and the spring constant. Not on the displacement.

Explanation:

Solution:

As we know that:

F = Kx

Here,

K = Spring constant

x = displacement.

First, they are displacing it with 6 cm from its rest position for which Time period of the oscillation is T = 2 seconds.

But next, they want to know the effect on the time period of the oscillation if the displacement x is doubled from 6cm to 12 cm.

First of all, let us see the equation of the time period of the oscillation.

We need to check, if time period does depend on the displacement or not.

As we know,

Time period of horizontal Oscillation  = T = 2[tex]\pi[/tex][tex]\sqrt{\frac{m}{k} }[/tex]

As you can see, from the equation, Period of oscillation depends upon the mass and the spring constant. Not on the displacement.

Since, K is the constant for a particular spring, we need to change the mass of the cart to change the time period.

Hence the Time period will remain same.

The time period will remain the same in both conditions. The time period of horizontal Oscillation will be [tex]2 \pi \sqrt{\frac{m}{k} }[/tex].

What is the time period of oscillation?

The period is the amount of time it takes for a particle to perform one full oscillation. T is the symbol for it. Taking the reciprocal of the frequency yields the frequency of the oscillation.

From Hooke's law;

F = Kx

Where,

K is the spring constant

x is the  displacement

First, they move it 6 cm from its rest position, with a T = 2 second oscillation period.

However, they want to know what influence doubling the displacement x from 6 cm to 12 cm has on the oscillation's time period.

Let's start by looking at the oscillation's time period equation. We need to see if the time period is affected by the shift.

The time period of the horizontal oscillation is given by;

[tex]\rm T = 2 \pi \sqrt{\frac{m}{k} }[/tex]

As the equation shows, the period of oscillation is determined by the mass and the spring constant. On the displacement, no.

We must modify the mass of the cart to change the time period since K is the constant for each spring.

Hence the time period will not change.

To learn more about the time period of oscillation refer to the link;

https://brainly.com/question/20070798

How does the geosphere interact with the biosphere during a fire?

Answers

Answer: A forest fire could affect the geosphere by ash and the heat from the fire, but the fire would affect the biosphere by less oxygen in the air and would make it hard for human to breath affecting climate change. Also many homes to wildlife that live in the forest would lose their homes. This would result in lose of money from no hunting and that affect the economy.

What happens to Average Speed if distance decreased & time stayed the same?

Answers

Answer:

I think you are trying to ask 'what happens to the average speed (of humans or animals.) if the distance decreased and time stayed the same (the time such as what hour it is or what second?)' If that is the case then the average speed will be more since the distance decreased. And the time staying the same might affect it I am not fully sure so I will not say anything about that. I hope this helps!

Various amplifier and load combinations are measured as listed below using rms values. For each, find the voltage, current, and power gains ( A v , Ai , and Ap, respectively) both as ratios and in dB:
(a) vI= 100 mV, iI = 100 μA, vO = 10 V, RL = 100Ω
(b) vI = 10 μV, iI = 100 nA, vO =1 V, RL= 10 kΩ
(c) vI =1 V, iI = 1 mA, vO =5 V, RL = 10Ω

Answers

Answer:

The solution to this question can be defined as follows:

Explanation:

In point (a):

[tex]v_i= 100 \ mV\\\\ i_I = 100 \mu \ A\\\\ v_O = 10 \ V\\\\ R_L = 100 \ \Omega \\\\i_L = \frac{V_0}{R_L} = \frac{10}{100} = 100 \ MA \\\\A_v = \frac{V_0}{V_i} = \frac{10}{100 \times 10^{-3}} =100 \\\\A_v(db) = 20 \lag (100) =40 \ db \\\\ A_i= \frac{i_L}{i_i} = \frac{100 \times 10^{-3}}{100 \times 10^{-6}} =1000 \\\\A_i(db) = 20 \lag (100) =60 \ db \\\\[/tex]

[tex]A_p= \frac{P_0}{p_i} =\frac{v_0 i_L}{v_i i_i} = \frac{ 10(100 \times 10^{-3})}{100 \times 10^{-6} \times 100 \times 10^{-3}} =100000\\\\ A_p(db) =10 \log (100000) =50 \ db \\\\[/tex]

In point (b):

[tex]v_i = 10 \mu V\\\\ i_i = 100 \ nA \\\\ v_O =1 \ V \\\\ R_L= 10 \ k \Omega \\\\i_0 = \frac{V_0}{R_L} = \frac{1}{10 \ K} = 100 \ \muA \\\\A_v = \frac{V_0}{V_i} = \frac{10}{10 \times 10^{-6}} =100000 \\\\A_v(db) = 20 \lag (100000) =100 \ db \\\\ A_i= \frac{i_0}{i_i} = \frac{100 \times 10^{-6}}{100 \times 10^{-9}} =1000 \\\\A_i(db) = 20 \lag (1000) =60 \ db \\\\[/tex]

[tex]A_p= \frac{P_0}{p_i} =\frac{v_0 i_0}{v_i i_i} = \frac{ 1 \times 100 \times 10^{-6})}{10 \times 10^{-6} \times 100 \times 10^{-9}} =100000000\\\\A_p(db) =10 \log (100000000) =80 \ db \\\\[/tex]

In point (C):

[tex]v_i =1\ V\\\\ i_I = 1 \ mA\\\\ v_O =5\ V \\\\ R_L = 10 \ \Omega \\\\i_0 = \frac{V_0}{R_L} = \frac{5}{10 } = 0.5 \ A \\\\A_v = \frac{V_0}{V_i} = \frac{5}{1} =5 \\\\A_v(db) = 20 \log 5 =13.97 \ db = 14 \db \\\\ A_i= \frac{i_0}{i_i} = \frac{0.5}{1\times 10^{-3}} =500 \\\\A_i(db) = 20 \log (500) =53.97 \ db = 54 \db \\\\[/tex]

[tex]A_p= \frac{P_0}{p_i} =\frac{v_0 i_0}{v_i i_i} = \frac{ 5 \times 0.5 }{1 \times 1 \times 10^{-3}} =2500\\\\A_p(db) =10 \log (2500) = 33.97 \ db = 34 \db\\\\[/tex]

Let w(x)=3x-7.If w(x)=14, find x

Answers

Answer:

7

Explanation:

We are given:

    w(x) = 3x   -   7

     w(x)  = 14

The problem here entails us to solve for x;

To solve for x; equate the two expressions:

         

          3x  - 7  = 14

           3x  = 14 + 7

           3x  = 21  

             x = 7

So the value of x  = 7

Some giant ocean waves have a wavelength of 25 m and travel at 6.5 m/s with a frequency of 0.26 HZ. What is the period of such a wave ?

Answers

Answer:

3.85s

Explanation:

Given parameters:

Wavelength = 25m

Velocity  = 6.5m/s

Frequency  = 0.26Hz

Unknown:

Period of the wave = ?

Solution:

The period of a wave is the inverse of the frequency of the wave.

    Period  = [tex]\frac{1}{frequency}[/tex]  

  Period = [tex]\frac{1}{0.26}[/tex]   = 3.85s

When the sum of all the forces acting on a block on an inclined plane is zero, the block
A) must be at rest
B) must be accelerating
C) may be slowing down
D) may be moving at constant speed

Answers

Answer:

hmmm thats too hard for me.

Explanation:

What is the gravitational force between two students, John and Mike, if John has a mass of 81.0 kg, Mike has a mass of 93.0 kg, and their centers are separated by a distance of .620 m?

Answers

Answer:

1.31×10¯⁶ N

Explanation:

From the question given above, the following data were obtained:

Mass of John (M₁) = 81 Kg

Mass of Mike (M₂) = 93 Kg

Distance apart (r) = 0.620 m

Gravitational constant (G) = 6.67×10¯¹¹ Nm²/Kg²

Force (F) =?

The gravitational force between the two students, John and Mike, can be obtained as follow:

F = GM₁M₂ / r²

F = 6.67×10¯¹¹ × 81 × 93 / 0.62²

F = 6.67×10¯¹¹ × 7533 / 0.3844

F = 1.31×10¯⁶ N

Therefore, the gravitational force between the two students, John and Mike, is 1.31×10¯⁶ N

Suppose Isaac Newton can swim with a velocity of 35 m/sec. If Isaac Newton swims straight
across a river with a current of 22 m/sec, then what is the magnitude of Newton's resulting
velocity as he swims across the river. Note: Sir Isaac Newton swims like Aquaman.

Answers

Answer:

Let Vx = 35 m/s     speed of swimmer across river

     Vy = 22 m/s     speed of river dowstream

V = (Vx^2 + Vy^2)^1/2 = 41.3 m/s      net speed of swimmer

tan theta = Vy / Vx = .629    theta = 32.2 deg

(Theta would be zero if speed of river was zero)\

PLEASE HELP IM HEING TIMED

Answers

Answer:

Uh, I could be wrong but doesn’t it mean that the wave and particle are reacting together to make light? I think it’s something like that... I hope this helps!

I will give brainly
Defend Democritus' work on the atom and its contribution to the modern atomic model.

Answers

Answer

Around 400 B.C.E, the Greek philosopher Democritus introduced the idea of the atom as the basic building block matter. Democritus though that atoms are tiny, uncuttable, solid particles that are surrounded by empty space and constantly moving at random.

Pls give me BRAINLIEST

The speed limit on some segments of interstate 4 is 70 mph. What is this in km/h?

Answers

Answer:

112.63km/hr

Explanation:

The given dimension is :

         70mph

We are to convert this to km/hr

         1 mile  = 1.609km

         

so;

     70mph x 1.609    = 112.63km/hr

So,

  The solution is 112.63km/hr

Artificial satellites in space can help you find locations on
Earth. True or false?

Answers

yes the answer is true

•What is the gravitational potential energy of a girl
who has a mass of 40 kg and is standing on the
edge of a diving board that is 5 m above the water?

Answers

Answer:

1960 joule

Explanation:

Plz help this is so confusing

Answers

The correct answer is 5 km/h

Explanation:

The speed at which the duck travels can be found by using the equation that is given (speed= distance/ time). The first step to do this is to replace distance and time using the values given. Here is the process:

speed = distance / time

speed = 10 km / 2 hours

Now, solve this equation

speed = 10 km/ 2 hours

10 / 2 or 10 divided 2 = 5

Finally, use the units, in this case, the correct units are km/h

a spring stretches from an initial height of 5 cm to a final stretch of 10 cm. the spring constant is 800 n/m.How much work was done on the spring?
what is the final force on the spring when it is at its 10 cm stretch?
explain why it is not appropriate to use the equation w=f//d when considering springs.

Answers

Answer:

.

Explanation:

F = kx so k = 800/((10-5)/100) = 16000 N/m

W = 1/2 kx^2 = 1/2 * 16000 * .05^2 = 20 J.

(sorry if it's wrong)

Heat traveling through a pan to warm food in the pan is an example of what kind of heat transfer?

A. Convection
B. Radiation
C. Insulation
D. conduction

Answers

Answer:

A

Explanation:

Answer:

D. Conduction

Explanation:

Convection heat transfer occurs in fluids, while conduction heat transfer occurs in solids.

A 62 kg student, starting from rest, slide down an 10.6 m high water slide. How fast is he going at the bottom of the slide? Use g = 10 m/s2

Answers

Answer:

14.6m/s

Explanation:

Given parameters:

Mass of the student  = 62kg

Initial velocity  = 0m/s

Height of slide = 10.6m

g  = 10m/s²

Unknown:

Speed at the bottom of the slide = ?

Solution:

The speed at the bottom of the slide is the final velocity;

             v ² = u²  + 2gh

v is the final velocity

u is the initial velocity

g is the acceleration due to gravity

h is the height

             v² = 0²  +  2x 10 x 10.6

             v²  = 212

              v  =  14.6m/s

Please answer this question I don't know how to do it.

Answers

One year = 365 days = 8760 hours = 525,600 minutes = 31,536,000 seconds

One light year = speed of light * 31,536,000 seconds

1340 light years = 1340 * one light year

A safety plug is designed to melt when the pressure inside a metal tank becomes too high. A gas
at 51.0 atm and a temperature of 23.0°C is contained in the tank, but the plug melts when the
pressure reaches 75.0 atm. What temperature did the gas reach?

Answers

The plug is 6 but u have to divert by the scale to form 5 .C

To review the solution to a similar problem, consult Interactive Solution 1.43. The magnitude of a force vector is 87.4 newtons (N). The x component of this vector is directed along the x axis and has a magnitude of 72.1 N. The y component points along the y axis. (a) Find the angle between and the x axis. (b) Find the component of along the y axis.

Answers

Answer:

(a) 34.4°

(b) 49.4 N

Explanation:

(a) From the diagram,

Amgle between the x axis can be calculated as,

cosΘ = adjacent/hypoteneous

cosΘ = 72.1/87.4

cosΘ = 0.8249

Θ = cos⁻¹(0.8249)

Θ = 34.4°.

Hence the angle between the x axis is 34.4°

(b) To find the component along the y axis we make use of pythagoras theorem.

a² = b²+c²................... Equation 1

Where a = 87.4 N, b = 72.1 N, c = y.

Substitute  these values into equation 1

87.4² = 72.1² + y²

y² = 87.4²-72.1²

y² = 2440.35

y = √(2440.35)

y = 49.4 N

A person's speed around the Earth is faster at the poles than it is at the equator.
True or False?

Answers

Answer:

no

Explanation:

it is faster at the equator

A uniform disk with mass 35.2 kg and radius 0.200 m is pivoted at its center about a horizontal, frictionless axle that is stationary. The disk is initially at rest, and then a constant force 34.5 N is applied tangent to the rim of the disk.
a) What is the magnitude v of the tangential velocity of a point on the rim of the disk after the disk has turned through .200 revolution?
b) What is the magnitude a of the resultant acceleration of a point on the rim of the disk after the disk has turned through .200 evolution?

Answers

Answer:

a) v = 1.01 m/s

b) a = 5.6 m/s²

Explanation:

a)

If the disk is initially at rest, and it is applied a constant force tangential to the rim, we can apply the following expression (that resembles Newton's 2nd law, applying to rigid bodies instead of point masses) as follows:

       [tex]\tau = I * \alpha (1)[/tex]

Where τ is the external torque applied to the body, I is the rotational inertia of the body regarding the axis of rotation, and α is the angular acceleration as a consequence of the torque.Since the force is applied tangentially to the rim of the disk, it's perpendicular to the radius, so the torque can be calculated simply as follows:τ = F*r (2)For a solid uniform disk, the rotational inertia regarding an axle passing through its center  is just I = m*r²/2 (3).Replacing (2) and (3) in (1), we can solve for α, as follows:

       [tex]\alpha = \frac{2*F}{m*r} = \frac{2*34.5N}{35.2kg*0.2m} = 9.8 rad/s2 (4)[/tex]

Since the angular acceleration is constant, we can use the following kinematic equation:

        [tex]\omega_{f}^{2} - \omega_{o}^{2} = 2*\Delta \theta * \alpha (5)[/tex]

Prior to solve it, we need to convert the angle rotated from revs to radians, as follows:

       [tex]0.2 rev*\frac{2*\pi rad}{1 rev} = 1.3 rad (6)[/tex]

Replacing (6) in (5), taking into account that ω₀ = 0 (due to the disk starts from rest), we can solve for ωf, as follows:

       [tex]\omega_{f} = \sqrt{2*\alpha *\Delta\theta} = \sqrt{2*1.3rad*9.8rad/s2} = 5.1 rad/sec (7)[/tex]

Now, we know that there exists a fixed relationship the tangential speed and the angular speed, as follows:

        [tex]v = \omega * r (8)[/tex]

where r is the radius of the circular movement. If we want to know the tangential speed of a point located on the rim of  the disk, r becomes the radius of the disk, 0.200 m.Replacing this value and (7) in (8), we get:

       [tex]v= 5.1 rad/sec* 0.2 m = 1.01 m/s (9)[/tex]

b)    

There exists a fixed relationship between the tangential and the angular acceleration in a circular movement, as follows:

       [tex]a_{t} = \alpha * r (9)[/tex]

where r is the radius of the circular movement. In this case the point is located on the rim of the disk, so r becomes the radius of the disk.Replacing this value and (4), in (9), we get:

       [tex]a_{t} = 9.8 rad/s2 * 0.200 m = 1.96 m/s2 (10)[/tex]

Now, the resultant acceleration of a point of the rim, in magnitude, is the vector sum of the tangential acceleration and the radial acceleration.The radial acceleration is just the centripetal acceleration, that can be expressed as follows:

       [tex]a_{c} = \omega^{2} * r (11)[/tex]

Since we are asked to get the acceleration after the disk has rotated 0.2 rev, and we have just got the value of the angular speed after rotating this same angle, we can replace (7) in (11).Since the point is located on the rim of the disk, r becomes simply the radius of the disk,, 0.200 m.Replacing this value and (7) in (11) we get:

       [tex]a_{c} = \omega^{2} * r = (5.1 rad/sec)^{2} * 0.200 m = 5.2 m/s2 (12)[/tex]

The magnitude of the resultant acceleration will be simply the vector sum of the tangential and the radial acceleration.Since both are perpendicular each other, we can find the resultant acceleration applying the Pythagorean Theorem to both perpendicular components, as follows:

       [tex]a = \sqrt{a_{t} ^{2} + a_{c} ^{2} } = \sqrt{(1.96m/s2)^{2} +(5.2m/s2)^{2} } = 5.6 m/s2 (13)[/tex]

need help pleaseee !

Answers

Answer:

08 and 09 with be 67

Explanation:

i know this because it was the vase major

Other Questions
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