The model of the atom has changed as scientists have gathered new evidence. Four models of the atom are shown below, but one important model is missing. An image at left with overlapping red and blue balls in the center with a circular fuzzy green cloud outside them. An image at center left with a purple ball in the center surrounded by overlapping concentric black ovals, each with a small green ball on each of the 6 ovals. An image at center right with a large black cross in a purple circle with a black line around the purple, with 10 small green balls dispersed within the purple circle. An image at right with a purple center outlined in black with two concentric black circles around the center, the inner circle having 2 small green balls on it and the outer circle having 8 small green balls on it. Which atomic model is missing from this set? Bohr’s model Dalton’s model Rutherford’s model Thomson’s model

Answer: Some of the ways to control noise pollution are as follows: (1) Control at Receiver's End (2) Suppression of Noise at Source (3) Acoustic Zoning (4) Sound Insulation at Construction Stages (5) Planting of Trees (6) Legislative Measures.

Answer:

You have to:

a) Improve your insulation.

b) Install a fence

c) Use modern Acoustic wall panels

d) Plant trees

e) Reduce electronic volumes,e.t.c.

Explanation:

okay.

Answer:

1) The balloon will shrink

2) The balloon will grow bigger and regain its shape

Explanation:

By the kinetic theory of gases, we have;

[tex]v_{rms} = \sqrt{\dfrac{3 \cdot R \cdot T}{MW} }[/tex]

[tex]P = \dfrac{n \cdot MW \cdot vrms^2}{3 \cdot V}[/tex]

Where;

[tex]v_{rms}[/tex] = RMS Speed

R = The universal gas constant

T = The temperature

MW = The Molecular weight

n = The number of moles

V = The volume

P = The pressure

1) When the balloon is placed in the refrigerator for  minutes, the temperature inside the balloon will drop and RMS speed will reduce, however due to the elastic wall of the balloon, the pressure will remain the same therefore the volume  will reduce and the balloon will shrink

2) When the balloon is placed on the kitchen counter, the temperature inside the balloon will rise leading to the increase in the RMS speed which will raise the pressure effect on the wall  of the balloon as the balloon is made of elastic material, as the pressure rises, the wall expands to keep the pressure constant and the volume occupied by the air particles will increase, the balloon will grow bigger and regain its shape.

Explanation:

Average speed = distance / time

v_avg = 47 km / 1.72 hr

v_avg = 27.3 km/hr

Answer:

is the last one, a magnetic wave and electrical current moving in opposite directions

Explanation:

opposite directions always attract in magnetic waves and fields

Answer:

I should be active for 15 hours to meet the physical activity requirement.

Explanation:

Since time dilates in moving objects, we use the formula t = t₀/√(1 - β²) where t = time in space vehicle, t₀ = time on earth = 9 hours and β = v/c where v = speed of space vehicle = 0.8c.

So, t = t₀/√(1 - β²)

t = 9/√(1 - (v/c)²)

= 9/√(1 - (0.8c/c)²)

= 9/√(1 - (0.8)²)

= 9/√(1 - (0.64)

= 9/√0.36

= 9/0.6

= 15 hr

So, according to a timer on the space vehicle, I should be active for 15 hours to meet the physical activity requirement.

Answer:

Transverse wave

Explanation:

Its because in transverse wave the particle displacement is perpendicular to the direction of wave propagation..hope it helps you...

Explanation:

Assuming the 10 m distance is the vertical displacement, the work done by both people is the same.

Work = force × distance

W = (250 N) (10 m)

W = 2500 J

The power of the first person is:

Power = work / time

P = 2500 J / 120 s

P = 20.83 W

The power of the second person is:

P = 2500 J / 60 s

P = 41.67 W

Answer:

The sound travels differently in different medium according the density of the medium.

Explanation:

The sound travels faster in dense medium and can be heard by the vibration of the bone present in the ear. The ear plugs reduce the sound intensity in both medium water and on land (air).

In air the sound is not heard properly due to the earplugs that stops the as the vibration are not able to produce as sound is not able to reach to middle ear, but Navy researchers have discovered that sound under water is heard by the bone present behind the ear, vibrations mastoid.

Answer:

This is called restricted speed

Answer:

Explanation:

It is the case of perfectly elastic collision . So we shall apply formula of velocity after collision as follows .

Let  m₁ and m₂ be the mass colliding with velocity u₁ and u₂ and their velocity become v₁ and v₂ after collision .

[tex]v_1=\frac{(m_1-m_2)u_1 }{m_1+m_2)} +\frac{2 m_2u_2}{(m_1+m_2)}[/tex]

Putting the values

[tex]v_1=\frac{ (.30-.80).40 }{( .30+.80)} +\frac{2\times .80\times(-.15) }{(.30+.80 )}[/tex]

= - 0.4 m /s

So direction of .30 kg mass will be reversed .

[tex]v_2=\frac{ ( m_2-m_1) u_2 }{( m_1+m_2)} +\frac{2 m_1u_1}{(m_1+m_2)}[/tex]

putting the values

[tex]v_2=\frac{ ( .80-.30)(-.15) }{( .30+.80)} +\frac{2 \times.30\times.40}{(.30+.80)}[/tex]

= .15 m /s

The direction of .80 kg will become from left to right ie its direction will be reversed .

b ) Minimum amount of kinetic energy will be at the position when they move with common velocity

common velocity

v = .3 x .4 - .8 x .15 / (.3 + .8)

= 0

c )

Missing energy is stored as elastic potential energy in the spring .

Answer:

Take up space

Explanation:

Actually we know this by the definition of matter which states that "matter is any substance that has mass and takes up space by having volume."

hope it helped you:)

Answer:

The retina comprises of rod and cone cells . The rod cells are responsible for black and white vision and require low light levels while the cone cells are responsible for color vision and require good/high light levels for better functioning.

When faint stars are looked at on the edges of the vision it allows more light from faint objects to strike the rod cells which then becomes more visible.

Answer:

Hey there!

Mixtures are physically combined and can be separated. For example, sand and water is a mixture.

Pure substances are samples of matter with definite, and unchangeable chemical properties. For example, diamond is a pure substance.

Let me know if this helps :)

a pure substance is a substance that has not been mixed with anything, a mixture has been mixed with another substance. an example is

dirt +water=mud iron is an example of a substance

Answer:

If I understand correctly. Line B is parallel to the circle. Also, the angle is less than 90.

'Circle' is characterized as "a two-dimensional geometric figure comprising of the set of all those points in a plane that are at equal distance from the center."

1). Line B would be considered as the 'tangent' in association with the given circle.

2). The angle lying among the lines A and B would be of 90° i.e. right angle.

Given that,

A circle with line A drawn through its center

Line B moves while touching the edge of the circle and intersects line A outside the circle.

Learn more about 'circle' here:

brainly.com/question/11833983

Answer:

9 kg

Explanation:

Momentum is mass times velocity.

p = mv

36 kgm/s = m (4 m/s)

m = 9 kg

The mass of the bicycle is 9 kg.

The momentum of the bicycle is the product of mass and velocity of the bicycle.

P = mv

where;

m = P/v

m = 36/4

m = 9 kg

Thus, the mass of the bicycle is 9 kg.

Learn more about momentum here: https://brainly.com/question/7538238

Answer:

The impulse exerted by one cart on the other has a magnitude of 4 N.s.

Explanation:

Given;

mass of the first cart, m₁ = 2 kg

initial speed of the first car, u₁ = 3 m/s

mass of the second cart, m₂ = 4 kg

initial speed of the second cart, u₂ = 0

Let the final speed of both carts = v, since they stick together after collision.

Apply the principle of conservation of momentum to determine v

m₁u₁ + m₂u₂ = v(m₁ + m₂)

2 x 3 + 0 = v(2 + 4)

6 = 6v

v = 1 m/s

Impulse is given by;

I = ft = mΔv = m(

The impulse exerted by the first cart on the second cart is given;

I = 2 (3 -1 )

I = 4 N.s

The impulse exerted by the second cart on the first cart is given;

I = 4(0-1)

I = - 4 N.s (equal in magnitude but opposite in direction to the impulse exerted by the first).

Therefore, the impulse exerted by one cart on the other has a magnitude of 4 N.s.

The answer is:

-5846.75

Answer:

x = 27.3 m

Explanation:

This is a projectile launching exercise, let's start by looking for the time it takes for the rock to reach the height of the window.

Let's use trigonometry to find the velocities of the rock

           sin 40 = [tex]v_{oy}[/tex] / v

           cos 40 = v₀ₓ / v

           v_{oy}= v sin 40

           v₀ₓ = v cos 40

           v_{oy} = 30 sin 40 = 19.28 m / s

           v₀ₓ = v cos 40

           v₀ₓ = 30 cos 40 = 22.98 m / s

we look for the time

        [tex]v_{y}^2[/tex] = v_{oy}^2 - 2 g y

         v_{y}^2 = 19.28 2 - 2 9.8 16 = 371.71 - 313.6 = 58.118

        v_{y} = 7.623 m / s

we calculate the time

          v_{y} = v_{oy} - gt

          t = (v_{oy} - v_{y}) / g

          t = (19.28 -7.623) / 9.8

          t = 1,189 s

since the time is the same for both movements let's use this time to find the horizontal distance

           x = v₀ₓ t

           x = 22.98 1,189

           x = 27.3 m

Answer:

Explanation:

Take note that when the fuel of the rocket is consumed, the acceleration would be zero. However, at this phase the rocket would still be moving up until all the forces of gravity would dominate and change the direction of the rocket. Hence, there will be a need to calculate two distances, one from the ground until the point where the fuel is consumed and from that point to the point where the gravity would change the direction.

Given:

a = 76.8 m/s^2

t = 1.99 s

Solution:

d = vi (t) + 0.5 (a) (t^2)

d = (0) (1.99) + 0.5 (76.8) (1.99)^2

d = 0+38.4×3.9601

d = 152.068m

vf = vi + at

vf = 0 + 76.8 (1.99)

vf = 152.83 m/s (velocity when the fuel is consumed completely)

Then, we calculate the time it takes until it reaches the maximum height.

vf = vi + at

0 = 152.83+(-9.8) (t)

0 = 152.83 + (-9.8) (t)

-152.83 = -9.8t

t = 152.83/9.8 s

t = 15.59s

Then, the second distance

d= vi (t) + 0.5 (a) (t^2)

d = 152.83 (15.59) + 0.5 (-9.8) (15.59^2)

d = 2382.6197- 1190.93

d = 1191.68m

Then, we determine the maximum altitude:

d1 + d2 = 152.068 m + 1191.68m = 1343.748m

Answer:

The name of the force is elastic (spring) force

Explanation:

The elastic force which is the restoration force of an elastic (spring like) object that tries to return to its initial non-stretched state built up by the pulling of the bow by the archer (using the muscles) pushes on the arrow which the archer releases the same time he leaves the bow string, and the arrow flies in the direction already pointed by the archer

The arrow ultimately falls down due to gravity forces that acts on all objects within the Earths gravitational field. However due to the speed of constant horizontal speed of the arrow and increasing downward speed of the due to the gravity force, the falling of the arrow looks disappointing.

Answer:

degrees

Explanation:

If a direction is somewhere between north and east, it is measured in degrees.

This measurement will be possible thanks to the existence of geographical coordinates that are some 'imaginary lines' that help us find our location on the earth's surface. These lines are called latitude and longitude, both of which are measured in degrees.

It is like a sea battle game where you have to combine the rows and columns in order to identify where the targets are located. Geographic coordinates work the same way, you must combine the rows and columns of the planisphere to identify the locations of the planet. So the lines would be the latitudes and the columns the longitudes.

Answer

As the angle of incidence increases in Figure 2.8, a point is finally reached where the refracted ray does not emerge at the second layer but lie along the interface. This particular angle of incidence at which the angle of refraction is 90° and the refracted ray lies along the interface is known as the critical angle. At and beyond the critical angle, there is no transmitted ray and therefore a very high reflected ray will be recorded .

Therefore,

sinθisin90=Vp1Vp2

But, sin 90 = 1.

At critical angle,

sinθcritical=Vp1Vp2

A critical refracted wave travels along the interface between layers and is refracted back into the upper layer at the critical angle. The waves refracted back into the upper layer are called head waves or first-break refractions because at certain distances from a source, they are the first arriving energy. Recorded first-break refraction is shown in Figure 2.10.

Note that these first-break refractions can give us important information about the shallow velocities on land seismic data.

Note also that seismic data are acquired in such a way that reflections from horizons of interest are in the pre-critical region, even at the farthest offset in the data.

In reality, part of the seismic energy arriving at an interface is transmitted and refracted, and another part of the energy is reflected at that same interface. Given that there are many reflectors in the subsurface, there will be many paths from source to receiver, each of them with a different travel time. The proportion of energy reflected depends on the material properties of the two bounding layers and on the angle of incidence

Answer:

External locus of control

Explanation:

External locus of control is an attitude people possess that makes them attribute their failures or successes to factors other than themselves. The opposite of this type of attitude is the Internal locus of control where the individuals take responsibility for the outcomes of their actions whether good or bad. One good thing about the external locus of control is that when the individuals with this characteristic record successes, they attribute it to others and this presents them as people with team spirit. However, when they record failures, they do not want to take the blame, but rather attribute it to others.

Fred exhibits an external locus of control because he attributed his speeding to other factors like the road signs and GPS instead of fully admitting that it was his fault.

Answer: Efficiency signifies a peak level of performance that uses the least amount of inputs to achieve the highest amount of output.

Explanation: It minimizes the waste of resources such as physical materials, energy, and time while accomplishing the desired output.

Answer:

The efficiency of a simple machine is defined as the ratio of useful work done by the machine ( output work) to the total work out into the machine ( input work).

Explanation:

If a machine overcomes a load ' L ' and the distance travelled by the load is 'Ld' , the work done by the load is L× LD. It is also called output work or useful work.

Therefore, [tex] \boxed{Output \: work \: = L \: \times \: Ld}[/tex]

Likewise, The effort applied to overcome the load is 'E' and the distance covered by effort is 'Ed' , the work done by effort is E × Ed. It is also called input work.

Therefore, [tex] \boxed{Input \: work = E \times Ed}[/tex]

The efficiency of a simple machine is defined as the ratio of output work to the input work .

Therefore, [tex] \boxed{Efficiency ( η)= \frac{outpt \: work}{input \: work} \times 100\%}[/tex]

Efficiency is expressed in percentage. It is a ratio of two works. A machine is never 100% efficient. It is because no machine is friction free and due to friction, some of the input energy is wastes in the form of heat energy.

[tex] \mathrm{Hope \: I \: helped!}[/tex]

[tex] \mathrm{Best \: regards!}[/tex]

Answer:

His conclusion best illustrates a pessimistic outlook.

Explanation:

As seen in the question above, Ken got 20% of his final grade in the first test he did for this class, that is, there will be other tests that can provide him to reach the grade needed to pass the class. However, even if there are possibilities, he believes that he will not pass the class, he does not have a positive and optimistic view of his future in this class and is sure that he will fail. This negative view of the future is an example of a pessimistic outlook.

Answer:

The collapse of a protostar with less than 0.08 times the mass of the Sun is halted by DEGENERACY PRESSURE. b. As a protostar shrinks in size, its central temperature rises along with its THERMAL PRESSURE. c. A star that has not yet finished forming is called a__PROTOSTAR_____. d. A forming star spins more rapidly as it collapses because of conservation of ANGULAR MOMENTUM. e. If a protostar has a mass too small for it to sustain nuclear fusion it becomes the type of object known as a____BROWN DWARF____

Answer:

integumentary, skeletal, muscular, nervous, endocrine, cardiovascular, lymphatic, respiratory, digestive, urinary, and reproductive

Explanation:

and this is biology not physics

Answer:

There will  be a huge problem of holding the wire strands together, and the power losses will also be amplified.

Explanation:

The force per unit length on two current carrying conductors, lying parallel to each other is proportional to the product of the current through the conductors, and inversely proportional to their distance apart. This force is attractive if the current flows through these conductors in the same direction, and is repulsive if it flows in the opposite direction.

For the strand of wire that make up a high voltage wire bundle, there will be a force of attraction pulling the wires closer to each other, and they will experience the maximum pulling force possible, since they lie next to each other. This force helps to hold these wires in a high tension wire strand together, limiting the area, and reducing "skin effect."

In the case that this wires in the wire strand acts in opposite of the known behavior, the wires will repel and push each other apart. This pushing apart will increase power loss due "skin effect" which is increased by an increase in exposed surface area of the wire strands. This will pose a big problem for high tension transmission.

Answer:

C) 1.5 A

Explanation:

P = IV

180 W = I (120 V)

I = 1.5 A

Answer:

[tex]r = \frac{v}{i} = v = ri \\ i = \frac{v}{r} [/tex]