the red lines on this
national weather
service weather map
connect areas of equal
air pressure. what do
meteorologists call
these lines?

a. isobars
b. cold fronts
c. air masses
d. isotherms

Answers

Answer 1
The circular lines you see on the chart are isobars, which join areas of the same barometric pressure.

Related Questions

Identify the reactions of the citric acid cycle that provide reducing power for the electron‑transport chain

Answers

The reactions of the citric acid cycle that provide reducing power for the electron‑transport chain are as follows:

Conversion of isocitrate to α-ketoglutarateConversion of succinate to fumarateConversion of α-ketoglutarate to succinyl-coA

What is citric acid cycle?

Citric acid cycle also known as kreb cycle is a series of biochemical reactions that involves the synthesis of reduced electron carrier and ATP.

The following steps in the citric acid cycle involves the provision of reducing power for the electron‑transport chain:

Conversion of isocitrate to α-ketoglutarate: Isocitrate is converted to α-ketoglutarate as catalyzed by isocitrate dehydrogenase. Conversion of α-ketoglutarate to succinyl-coA: α-ketoglutarate is converted to succinyl-coA as catalyzed by α-ketoglutarate dehydrogenase.

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The reactions of the citric acid cycle which provide reducing power for the electron‑transport chain are:

Conversion of isocitrate to α-ketoglutarateConversion of α-ketoglutarate to succinyl-coAConversion of succinate to fumarate.

Which citric acid cycle, provide reducing power?

Citric acid cycle, is the tricarboxylic acid cycle (TCA), which is the combination of chemical reaction. This reaction is necessary to produce the energy in aerobic organisms.

The reactions of the citric acid cycle which provide reducing power for the electron‑transport chain are:

Conversion of isocitrate to α-ketoglutarateConversion of α-ketoglutarate to succinyl-coAConversion of succinate to fumarate.

Hence, the option 1,3 and 4 is correct.

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A crane lifts a 450 kg concrete to the top of a 50 m building in 5 s.
Assuming g= 10 m/s
)
2
a) The potential energy of the concrete.
, calculate;
b) The power developed by the crane

Answers

Explanation:

Given : m=600kg h=20 m

Time of operation t=2 min =120 s

Work done in lifting a box W=mgh=600×10×20=120000

Power required P=

t

W

=

120

120000

=1000 watts

The kinetic energy of a javelin is 81 J, and its speed is 9.0 m/s. What is its mass?

A. 0.5 kg

B. 1.0 kg

C. 2.0 kg

D. 9.0 kg

Answers

Answer:

2 kg

Explanation:

K.E. = 1/2 m v^2

81   = 1/2  m (9^2)

1 = 1/2 m

m = 2 kg

What are the two conditions for equilibrium of a rigid body? how would this experiment demonstrate their validity?.

Answers

Answer:

They're are Conditions .... (L00K D0WN.)

Explanation:

Conditions for equilibrium require that the sum of all external forces acting on the body is zero (first condition of equilibrium), and the sum of all external torques from external forces is zero (second condition of equilibrium). These two conditions must be simultaneously satisfied in equilibrium.

100 Points!!!
1.) What does the image of an object look like through a convex lens when the object is further from the lens than the focal point?


A. It looks the same as the actual object.

B. It is right side up and larger than the object.

C. It is upside down and larger than the object.

D. It is upside down and smaller than the object.


2.) What happens when light rays reflect?


A. They are partially absorbed.

B. They bounce back.

C. They are all absorbed

D. They pass through an object.


3.) Based on how it refracts light, what would you expect images formed by a concave lens to look like?


A. Smaller

B. The same as the objects that they are images of

C. Magnified

D. Reversed


4.) What happens to light rays when they enter a different medium?


A. They reflect

B. They Bend

C. They Curve

D. They Stop

Answers

(1) The image of an object placed further from the lens than the focal point will be upside down and smaller than the object.

(2) When light rays reflect, they bounce back.

(3)  Images formed by a concave lens will look magnified.

(4) When light rays enter a different medium, they bend.

1.0 Object placed further from the lens than the focal point

The image of an object placed further from the lens than the focal point will be diminished and inverted.

Thus, the correct answer will be "upside down and smaller than the object".

2.0 What is reflection of light?

The ability of light to bounce back when it strike a hard surface is known as refection.

3.0 Image formed by concave lens

A concave lens is diverging lens is usually virtual, erect and magnified.

4.0 Refraction of light

The change in speed of light when it travels from medium to another medium is known as refraction. Refraction is also, the ability of light to bend around obstacles.

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Answer:

It is upside down and larger than the object

They bounce back

Magnified

They bend

Explanation:

What does it mean for forces to be in equilibrium?.

Answers

Explanation:

If the size and direction of the forces on the object are exactly balanced , then there is no net force acting on the object

A coin has a mass of 7.0g. It is made of a metal alloy of density 5.6g/cm3. Calculate the volume of the coin.

Answers

Volume = mass/density

Converting grams to kilograms
7.0 = 0.007
5.6 = 0.0056

Volume = 0.007/0.0056
Volume = 1.25 m^3

[tex]\text{Density,}\\\\~~~~~~~~\rho = \dfrac mV\\\\\\\implies V = \dfrac m{\rho}\\\\\\\implies V = \dfrac{7 \times 10^{-3}~ \text{kg}}{\tfrac{5.6 \times 10^{-3}~ \text{kg}}{ 10^{-6} ~\text{m}^3} }\\\\ \\\implies V = \dfrac{7 \times 10^{-3}~ \text{kg}}{5.6 \times 10^{-3} \times 10^6~~ \text{kg}~ \text{m}^{-3}}\\\\\\ \implies V = 1.25 \times 10^{-6}~ \text m^3\\\\\\\implies V =0.00000125~ \text m^3\\\\\text{Hence the volume of the coin is 0.00000125}~ \text m^3[/tex]

When using a different calorimeter, and mixing 50 ml of hot water at 65 degrees c with 60 ml of water in the calorimete

Answers

The specific heat capacity of the calorimeter used in mixing the water is determined as 21.87 J/g⁰C.

Conseervation of energy

The heat capacity of the calirometer is determined by applying the principle of conservation of energy.

Heat lost by the hot water = Heat gained by the calirometer

[tex]Q _w = Q_c\\\\M_w C_w\Delta \theta _w = M_c C_c\Delta \theta _c[/tex]

where;

M is mass

mass = density x volume = ρV

Density of water = 1 g/ml

Mass of hot water = 1 x (50) = 50 g

Mass of water in calorimeter = 1 x (60) = 60 g

Equilibrium temperature

[tex]\Delta T_c = 5.5\\\\T - 25 = 5.5\\\\T = 30.5 \ ^0C[/tex]

Specific heat capacity of the calirometer

[tex]50 \times 4.184 \times (65 - 30.5) = 60 \times C_c \times (30.5 - 25)\\\\7217.4 = 330C_c\\\\C_c = \frac{7217.4}{330} \\\\C_c = 21.87 \ J/g^0C[/tex]

Thus, the specific heat capacity of the calorimeter used in mixing the water is determined as 21.87 J/g⁰C.

The complete question is below

When using a different calorimeter, and mixing 50 ml of hot water at

65 degrees C with 60 ml of water in the calorimeter at 25 degrees C, the temperature of the calorimeter increased by 5.5 degrees C.

a. Calculate the heat capacity of this calorimeter?

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When a skydiver falls towards the Earth, the force of gravity from Earth pulls her towards the
Earth and she is obviously accelerating towards the Earth.
Can the reverse (the force of gravity pulls the Earth towards her and the Earth is accelerating
towards her) be true? Explain.

Answers

Answer:

yes

true

Explanation:

because earth is rotation

how fast would u have to throw a baseball for it to catch on fire? (explanation in step by step equations)

Answers

Explanation:

Multiply the time by the acceleration due to gravity to find the velocity when the object hits the ground. If it takes 9.9 seconds for the object to hit the ground, its velocity is (1.01 s)*(9.8 m/s^2), or 9.9 m/s

Answer:

800 feet per sec.

Explanation:

Converting it over from 105.1mph to ft per sec is only about 154.15fps.

If a runner exerts 457 j of work to make 321 w of power then how long did it take the runner to do the work

Answers

The time taken by the runner to do the work is 1.42 seconds.

Given the data in the question;

Work done; [tex]W = 457J[/tex]Power; [tex]P = 321W[/tex]Time elapsed; [tex]t = \ ?[/tex]

Power

Power can be simply referred to as the quantity of energy transferred per unit time.

It is expressed as;

[tex]P = \frac{W}{t}[/tex]

Where W is work done and t is time elapsed.

To determine the time it took the runner to do the work, we substitute our given values into the expression above.

[tex]P = \frac{W}{t} \\\\t = \frac{W}{P} \\\\t = \frac{457J}{321W} \\\\t = \frac{457 kgm^2/s^2}{321 kgm^2/s^3}\\\\t = 1.42s[/tex]

Therefore, the time taken by the runner to do the work is 1.42 seconds.

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The physical meaning of 220 volts​

Answers

Answer:

a particular level of electical potential from a power source

A thundercloud has an electric charge of 48.8 C near the top of the cloud and –41.7 C near the bottom of the cloud. The magnitude of the electric force between these two charges is 7980000 N. What is the average separation between these charges

a/ 1.51 km
b/ 2.53 Km
c/ 1.51 m
d/ 1001 m

Answers

Answer: 1.51 km

Explanation:

Coulomb's Law: The electrostatic force between two charge particles Q: and Q2 is directly proportional to product of magnitude of charges and inversely proportional to square of separation distance between them.

Or,   [tex]\vec{F}=k \frac{Q_{1} Q_{2}}{r^{2}}[/tex]

Where Q1 and Q2 are magnitude of two charges and r is distance between them:

Given:

Q1 = Charge near top of cloud = 48.8 C

Q2 = Charge near the bottom of cloud = -41.7 C

Force between charge at top and bottom of cloud (i.e. between Q: and Q2) (F) = 7.98 x 10^6N

k = 8.99 x 109Nm^2/C^2

So,

[tex]\begin{aligned}&7.98 \times 10^{6}=\left(8.99 \times 10^{9} \mathrm{Nm}^{2} / \mathrm{C}^{2}\right) \frac{48.8 \mathrm{C} \times 41.7 \mathrm{C}}{\mathrm{r}^{2}} \\&r=\sqrt{\frac{1.8294 \times 10^{13}}{7.98 \times 10^{6}}}=1.514 \times 10^{3} \mathrm{~m}=1.51 \mathrm{~km}\end{aligned}[/tex]

Therefore, the separation between the two charges (r) = 1.51 km

The average speed of a car that travels 100 miles in 4 hours is

Answers

speed = distance / time

speed = 100miles / 4hrs

speed = 25mph (miles per hour)

Use F = 1/T as your basis:
10. A stroboscope is set to flash every 8.00×10−5s. What is the frequency of the flashes?

The answer is 12,500 Hz but please show your work.

Answers

Time=T=8×10^-5s

Now

[tex]\\ \rm\rightarrowtail \nu=\dfrac{1}{T}[/tex]

[tex]\\ \rm\rightarrowtail \nu=\dfrac{1}{8\times 10^{-5}}[/tex]

[tex]\\ \rm\rightarrowtail \nu=0.125(10^5)[/tex]

[tex]\\ \rm\rightarrowtail \nu=12500s^{-1}[/tex]

[tex]\\ \rm\rightarrowtail \nu=12500Hz[/tex]

What is involved when water changes from one phase to the next?








a
thermal energy
b
indirect energy
c
finite energy
d
ideal gas laws

Answers

The Sun provides the energy to power the water cycle. When water changes state in the water cycle, the total number of water particles remains the same. The changes of state include melting, sublimation, evaporation, freezing, condensation, and deposition.

Thermal energy is involved when water changes from one phase to the next. Option A is correct.

What is latent heat ?

Latent heat is the heat needed for the phase change . When the temperature remains constant during melting or boiling, the added energy is employed in the phase change process.

The total number of water particles remains constant when water changes states throughout the water cycle.

When water alterations from one phase to the next, thermal energy is involved. Latent heat is the storage of thermal energy.

Hence, option A is correct.

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Why does a magnet exert force on another magnet when the two magnets are not in contact?

Answers

Answer:

1. Why does a magnet exert force on another magnet when the two magnets are not in contact? The magnetic field from north to south increases when they're closer together, and when they repel the repelling force increases as well. This is all due to the magnetic field.

Correct me if I'm wrong, Hope this helps

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By which factor is the sound intensity decreased at 3 meters?

StartFraction 1 over 9 EndFraction.
StartFraction 1 over 3 EndFraction.
StartFraction 1 over 2 EndFraction.
StartFraction 1 over 4 EndFraction.

Answers

Distance is the factor that decreased the sound intensity.

Which factor decrease sound intensity?

As a sound wave carries its energy through a  medium, the intensity of the sound wave decreases with increasing distance from the source.

So we can conclude that distance is the factor that decreased the sound intensity.

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By a factor of 1/9, the sound intensity decreased at 3 meters. Option A is correct,

What is the relation between sound intensity and distance?

Sound intensity is inverse proportional to the square of the distance.

The intensity of the sound is;

[tex]\rm I = \frac{1}{d^2} \\\\ \rm I = \frac{1}{3^2} \\\\ I=\frac{1}{9}[/tex]

By a factor of 1/9, the sound intensity decreased at 3 meters.

Hence, option A is correct,

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Question 1(Multiple Choice Worth 2 points)
(04.05 LC)
The number of protons plus the number of neutrons in an atom is equal to its
O atomic number
O mass number
O nuclear model
O energy level
Question 2 Multiple Choice Worth 2 points)

Answers

Answer: Mass Number

Explanation:

Atomic number is the number of just protons;

Nuclear Model is a theoretical description of what an atom looks like;

Energy levels are the energy states that electrons are in;

However, mass number is by definition the number of protons + number of neutrons. :)

If the electric potential in a region is given by v(x)=7/x2 the x component of the electric field in that region is

Answers

Hi there!

Recall that:
[tex]\Delta V = -\int\limits^a_b {E \cdot } \, dx[/tex]

Given an electric field, the potential difference can be solved by using integration. Similarly:
[tex]E = -\frac{dV}{dx}[/tex]

We can differentiate the electric potential equation to solve for the electric field.

Use the power rule:
[tex]\frac{dy}{dx} x^n = nx^{n - 1}[/tex]

Differentiate the given equation.

[tex]-\frac{dV}{dx}\frac{7}{x^2} =- \frac{dV}{dx}7x^{-2} = -(-14x^{-3}) = \frac{14}{x^3}[/tex]

Or:
[tex]\boxed{E(x) = \frac{14}{x^3}}[/tex]

The component of the electric field in that region is E = 14/x³ if the electric potential in a region is given by v(x)=7/x2

What is an electric field?

An electric field is an electric property that is connected with any location in space where a charge exists in any form. The electric force per unit charge is another term for an electric field.

We have:

The electric potential in a region is given by:

[tex]\rm V(x) = \frac{7}{x^2}[/tex]

We know the relation between potential difference and an electric field is given by:

[tex]\rm \triangle V = \int\limits^a_b {E.} \, dx[/tex]

If the electric field is given, then:

[tex]\rm E = -\frac{dV}{dx}[/tex]

[tex]\rm E = -\frac{d(7x^{-2} )}{dx}[/tex]

After differentiate:

[tex]\rm E = -(-14x^{-3})[/tex]  or

[tex]\rm E = \frac{14}{x^3}[/tex]

Thus, the component of the electric field in that region is E = 14/x³ if the electric potential in a region is given by v(x)=7/x2

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A 10-A current is maintained in a simple circuit with atotal resistance of 209 ohm. What net charge passes through any point in a circuit during a 1-minute interval?

Answers

Answer:

I = Q / t          definition of current I

Q = i t = 10 Coul/sec * 60 sec = 600 Coul

A 10-A current is maintained in a simple circuit with a total resistance of 209 ohms, then the net charge passes through any point in a circuit during a 1-minute interval would be 6000 Coulombs.

What is an electric charge?

Charged material experiences a force when it is exposed to an electromagnetic field due to the physical property of electric charge. You can have a positive or negative electric charge.

Electric current is defined as the charge per unit of time.

The mathematical relation between current and the electric charge

I =Q/T

Let us first convert the time period of minutes into seconds

1 min = 60 seconds

10  min = 10*60 seconds

            =600 seconds

Q = I*t

   =10*600

   =6000 Amperes

Thus, the net charge that passes through any point in a circuit during a 1-minute interval would be 6000 Amperes.

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the connection between a medium and a mechanical wave

Answers

Answer:

The energy of a mechanical wave can travel only through matter. The matter through which the wave travels is called the medium (plural, media). The medium in the water wave pictured above is water, a liquid. But the medium of a mechanical wave can be any state of matter, even a solid.

Explanation:

Brainlest pls if can thank you ! i hope its helped

Pls help with physics.
Question: How does kicking a soccer ball relate to newton's third law?
Thank you!

Answers

Answer:

Explanation: “Every action has an equal opposite reaction” is Newton’s third law. So in this situation, kicking the soccer ball is the action and the reaction is it rolling.

Answer:

you push against the ball and the ball pushes back at you

Your force->|<- ball's force

Explanation:

For every action, there is an equal and opposite reaction


Matthew drops a cherry pit out the car window 1.0m above the ground while traveling down the road at 18m/s.
a) How far, horizontally, from the initial dropping point, will the pit hit the ground
b) Draw a picture of the situation.
c) If the car continues to travel at the same speed, where will the car be in
relation to the pit when it lands?

Answers

Answer:

ADD ALL THEM AND ANSER WILL BE THERE 19.O

Explanatio

A 120 N accelerates an object 1. 2 m/s? What is the mass of the object?

Answers

Answer:

m = 100 kg

Explanation:

F = ma

120 = m × 1.2

m = 120 ÷ 1.2

m = 100 kg

An archer shot a 0.04 kg arrow at a target. The arrow accelerated at 7,000 m/s2 to reach a speed of 60.0 m/s as it left the bow. How much force did the arrow have?

Answers

The force at which the arrow moved when an archer shot a 0.04 kg arrow at a target is 280 N.

What is force?

Force is the product of mass and acceleration.

To calculate the amount of force the arrow moves, we use the formula below.

Formula:

F = ma............ Equation 1

Where:

F = Force m = mass of the arrowa = acceleration of the arrow.

From the question,

Given:

m = 0.04 kga = 7000 m/s²

Substitute these values into equation 2

F = 0.04×7000F = 280 N

Hence, the force at which the arrow moved is 280 N.

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Helppppp
5) Experimental Design Cavendish's homemade apparatus gave him a calculated
value for the Gravitational Constant of 6.74E-11 Nm²/kg? The accepted value today
(with 200 years more advanced technology) is 6.67E-11 Nm²/kg? What sources of
error might Cavendish have had? How might scientists have improved this
experiment over the years.

Answers

Answer:

The apparatus would need to be extremely delicate because of the very small values being measured, the gravitational attraction of two massive objects.

(I) the torsion constant, measuring the deflection of massive objects would be very small and difficult to measure accurately

(II) since all surrounding objects are massive, it is difficult to remove the effect of such objects from forces being measured

(III) to consider a massive object as having all of its mass at its center, the massive object would need to be uniform throughout - any nonuniformity of the object would affect the calculations

(IV) all physical measurements would need to be made with utmost accuracy because of the relatively small distances involved with regard to the extremely small force being measured

(V) today laser measurements would assist in measuring small deflections accurately

Suppose you have a 100 mhz cpu and a a/d converter with an 8 khz sampling rate. Samples of the a/d converter are 32-bits

Answers

The sampling rate that's given regarding the CPU will produce a rate of 256kps.

How to calculate the rate?

The following can be gotten from the question:

Sampling rate = 8KHx

Number of bits = 32

The data rate will be:

= 32 × 8kbps

= 256kps

In conclusion, the sampling rate that's given regarding the CPU will produce a rate of 256kps.

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The sampling rate specified for the CPU will result in a 256kb/s rate.Sampling rate is also known as the sampling frequency.

What is sampling rate?

The number of samples per second collected from a continuous signal to create a discrete or digital signal is referred to as sampling rate or sampling frequency.

The given data in the problem is;

Sampling rate= 100 mhz cpu

Number of  bits=32

The rate of the data is;

[tex]\rm R = 32 \times 8 kb/ s \\\\ \rm R = 256 kb / s \\\\[/tex]

Hence the sampling rate specified for the CPU will result in a 256kb/s rate.

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In most cultures, the difference between the majority viewpoint and the minority viewpoint is that the majority group is made to feel __________ and the minority group is made to feel __________. A. Divergent. . . Normal B. Equal. . . Superior C. Superior. . . Equal D. Normal. . . Divergent Please select the best answer from the choices provided A B C D.

Answers

The difference between the majority viewpoint and the minority view is that the majority group is made to feel normal and the minority group is made to feel divergent.

What is the viewpoint?

A vantage point or point of view from which something is viewed or assessed is known as the viewpoint The story is narrated from a variety of perspectives, including two major ones and several smaller ones.

Most studies comparing majority versus minority influence argue the author, places a premium on influence in the sense of prevailing. In this context.

There is evidence that majorities have greater public influence than minorities, and that minority impact when it happens, is mostly latent. In the current version,

Hence the difference between the majority viewpoint and the minority view is that the majority group is made to feel normal and the minority group is made to feel divergent.

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    Answer:  D        

Explanation:

Simplified for you.

Martha wants to calculate an object's velocity. What will she need to do?​

Answers

Answer:

you divide the distance by the time it takes to travel that same distance, then you add your direction to it.

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