The Doppler effect a. can be applied only to sound waves. b. is the basic explanation for the blue shift of light in our Universe. c. occurs when the frequency of sound waves received is lower if the wave source is moving toward you than if it's moving away. d. occurs when the pitch of a sound gets lower if the source is receding.

Answer:

400k

Explanation:

Formula for KE = [tex]\frac{1}{2} mv^{2}[/tex]

Plug in:

KE =  [tex]\frac{1}{2} mv^{2}[/tex]

KE =  [tex]\frac{1}{2}[/tex] × 2000 × 20^2

Solve:

1000 × 400 = 400,000 or 400k

Hope this helped.

Answer : 400000J OR 4×10^4J

Kinetic energy= 1/2mv^2

Here, m=2000kg; V=20m/s

1/2×2000×20×20=400,000J

Answer:

fhaiisjrbekxkrkebxnsiiwj4bnds

Answer:

It is already balanced

Explanation:

It is already balanced

Answer:

Cause of Inertia of Motion

Explanation:

It can be explained as follows...when the moving bus suddenly stops, the lower part of the body of the passenger contact with the bus suddenly comes to rest while the upper part of the body tends to retain its state of motion due to inertia. As a result, the passenger is thrown forward.

Answer:

The elements are grouped into the different substances by color. As you can see, Lithium, Beryllium, Sodium, Magnesium, Aluminum, Potassium, and Calcium are metals out of the first 20 elements.

Hydrogen, Helium, Carbon, Nitrogen, Oxygen, Fluorine, Neon, Phosphorus, Sulfur, Chlorine, and Argon, are non-metals within the first 20 elements.

Boron and Silicon count as Metalloids in the Periodic Table (properties of both metals and non-metals)

reference- socatric q and a

Explanation:

Answer:

(11-13) - Metals

(14) - Metalloid

(15-18) - Non- metals

(19-20) - Metals

Explanation:

The elements from 11 to 13 are metals. They are Sodium(Na), Magnesium(Mg) and Aluminum(Al) respectively.

The element 14 is a metalloid. It’s Silicon(Si).

The elements from 15 to 18 are non metals. The 18th element is a noble gas known as Argon(Ar).

The elements from 15 to 17 are Phosphorus(P), Sulphur(S) and Chlorine(Cl).

The elements from 19 to 20 are metals. They are Potassium(K) and Calcium(Ca).

Answer:

A turndra B rainforest

Explanation:

Answer:

MgO relative atomic mass is 40

Explanation:

Mg=24

O=16

Answer: 40 grams, if it is two grams per mL and you have 20 mL, you multiply 2 grams/mL and you get the answer

Answer:

Acceleration is 0.

Explanation:

Since the girl is running with a uniform velocity, meaning she is moving at a constant rate, she is not accelerating. Acceleration only occurs when the speed of an object increases, decreases, or if there is a change in direction.

We know

[tex]\boxed{\sf W=Fscos\theta}[/tex]

[tex]\\ \sf\longmapsto W=25(20)cos30°[/tex]

[tex]\\ \sf\longmapsto W=500\times \dfrac{\sqrt{3}}{2}[/tex]

[tex]\\ \sf\longmapsto W=250\sqrt{3}[/tex]

[tex]\\ \sf\longmapsto W=250(1.73)[/tex]

[tex]\\ \sf\longmapsto W\approx 430J[/tex]

Option a) 430 J work done he do after walking 20.0 m.

Work, in physics, is a measure of energy transfer that happens when an object exists moved over a distance by an external force at least part of which exists involved in the direction of the displacement.

Displacement exists as the distance moved in a straight line, in a provided direction, from the starting point. Displacement exists as a vector quantity as it includes size and direction.

An angle stands the figure formed by two rays, named the sides of the angle, sharing a standard endpoint, named the vertex of the angle.

⇒[tex]W=Fcos\theta[/tex]

⇒[tex]W=25(20)cos 30^{0}[/tex]

Then,

⇒[tex]W=50*\sqrt{3} /2[/tex]

⇒[tex]W=250\sqrt{3}[/tex]

Hence,

⇒[tex]W=250(1.73)[/tex]

[tex]W[/tex] approximately 430J.

Hence, Option a) 430 J work done he do after walking 20.0 m.

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Here are the observations

Sugar:-

Corn syrup:-

Oil:-

Answer:

Resultant force is 20 N

Explanation:

Resolving vertically:

[tex]{ \sf{F_{y} = (8 \cos 30 \degree) + (12 \cos 30 \degree) }} \\ { \sf{ \sum F_{y} = 17.3 \: newtons }}[/tex]

Resolving horizontally:

[tex]{ \sf{F_{x} = (8 \sin 30 \degree) + (12 \sin 30 \degree) }} \\ { \sf{ \sum F _{x} = 10 \: newtons}}[/tex]

Resultant force:

[tex]{ \boxed{ \bf{F = \sqrt{ {F _{x} }^{2} + {F _{y} }^{2} } }}} \\ { \sf{F = \sqrt{ {17.3}^{2} + {10}^{2} } }} \\ { \sf{F = \sqrt{399.29} }} \\ F = 19.98 \approx20 \: newtons[/tex]

Answer:

The MKS (metre, kilogram, second) system of units is the fundamental core of the SI (Systeme Internationale, or International System) of measurement. As various fields grow new forms of measurements based on MKS, terms or exact definitions may vary in different scientific or engineering disciplines. These inconsistencies are sorted out by the international committee that defines the SI system of units and keeps it up to date.

So the MKS is the static core, and the SI is the evolving, growing system of metric measurement.

Metres and kilograms were introduced after the French Revolution around 1790. Seconds were added by the 1830s, building the MKS system. More units came later. By 1948, a need was seen to develop a clear and consistent set of terms for measurement, and this led to 12 years of work, ending with the release of the first version of the SI in 1960.

The SI now has seven base units of measure. It begins with the original three metre, kilogram, and second, and adds the ampere for electricity, candela for light, kelvin for temperature, and mole for amount (number of atoms or molecules) of a substance.

The SI defines how each fundamental unit can be measured or obtained experimentally. These definitions have changed over time. For example, the metre was originally a measure related to the circumference of the Earth, then a set number of waves of a particular wavelength, and now a distance traveled by light in a vacuum in a certain period of time.

The SI also defines modifying terms such as milli-, centi-, and kilo- that are a specific number of each unit.

The SI includes many other derived units, as well.

By standardizing international use of measurements across different fields of science and engineering, the SI reduces confusion that would slow scientific progress and error that can produce engineering catastrophe such as the loss of the Mars Climate Orbiter in 1999 due to a table that should have been in metric units (kilograms and meters) being provided in United States customary units (pounds and inches).*

The Mars Climate Orbiter and its mission were lost due to a failure to use SI units consistently.

Hope this help you!:)

Explanation:

A parallel circuit is often called a current divider for its ability to proportion—or divide—the total current into fractional parts. Once again, it should be apparent that the current through each resistor is related to its resistance, given that the voltage across all resistors is the same

The process of PLACING a compass wherever you want it involves Biology.  Biology deals with everything that has to happen for your brain to send instructions to your muscles, your muscles to operate your arm and your hand, and your hand to move the compass to where you want it, while your eyes keep track of what's happening and send course-corrections through your brain.

Once you get the compass there and see it start doing strange things, those EFFECTS are explained by laws of nature that are covered in Physics.

Placing a compass near a wire with live electrical current involves physics. Because, the deflection in magnetic field by the current from the electrical wire is dealt with physics.

A magnetic field is generated by the field lines originating from a magnet or an electrical  coil. The moving current is always associated with a magnetic field.

A compass acts as a tiny magnet and it deflects to the north in  the absence of an electrical field. If an electric field is brought in contact with the compass the needle will deflect into the direction of the magnetic field from the wire.

The strength of a magnetic field, associated electric field, magnetic flux etc. are more focused in the branches of physics. The magnetic properties of a substance is a physical property.

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Answer:

16.50 m/s²

Explanation:

initial velocity(u)=45.2 m/s

final velocity(v)= 0 (it stops)

time taken(t)= 2.74 s

now,we have

acceleration(a)= (v-u)/t

= (0-45.2 m/s)/2.74s

= -45.2 m/s / 2.74s

= -16.50 m/s²

Answer:

[tex]\boxed {\boxed {\sf -16.5 \ m/s^2}}[/tex]

Explanation:

We are asked to find the acceleration of a man driving. Acceleration is the change in velocity over the change in time. Acceleration is calculated with the following formula.

[tex]a= \frac{v_f- v_i}{t}[/tex]

The driver's initial velocity is 45.2 meters per second. His final velocity is 0 meters per second because he came to a stop. He stopped in 2.74 seconds.

[tex]\bullet \ v_f= 0 \ m/s \\\bullet \ v_i= 45.2 \ m/s \\\bullet \ t= 2.74 \ s[/tex]

Substitute these values into the formula.

[tex]a= \frac{0 \ m/s - 45.2 \ m/s }{ 2.74 \ s}[/tex]

Solve the numerator by subtracting.

[tex]a= \frac{- 45.2 \ m/s }{ 2.74 \ s}[/tex]

[tex]a= -16.49635036 \ m/s^2[/tex]

The original measurements of velocity and time have 3 significant figures, so our answer must have the same. For the number we calculated, that is the tenths place. The 9 in the hundredth place tells us to round the 4 in the tenths place up to a 5.

[tex]a \approx -16.5 \ m/s^2[/tex]

The acceleration is approximately -16.5 meters per second squared. The acceleration is negative because the man slowed down and came to a stop.

Answer:

[tex]{ \bf{mechanical \: adv = \frac{load}{effort} }}[/tex]

Gamma rays

used in radiotherapy

Answer:

A body having uniform velocity has zero acceleration because

there is not change in velocity.

Answer:

d. No, porque la ecuación de trabajo lo define.

Explanation:

En Física, el trabajo realizado se puede definir como la cantidad de energía transferida cuando un objeto o cuerpo se mueve a lo largo de una distancia debido a la acción de una fuerza externa.

Matemáticamente, el trabajo realizado viene dado por la fórmula;

[tex] W = F * d [/tex]

Dónde;

Por lo tanto, podemos deducir de la definición de trabajo y su fórmula que el trabajo se realiza cuando un objeto (cuerpo) se mueve una distancia o experimenta cualquier forma de desplazamiento mientras transfiere energía.

Answer:

Because the air can move out of the balloon at such a speed, it propells the balloon forward.

Explanation:

SmolFox no longer exists

~Chad~

The action of the balloon pushes against the balloon moving it in the backward direction

Newton's third law of motion states that every action have a equal and opposite reaction . If object A  exert force on object B , then object B will also exert an equal and opposite force on object A . Forces result from interaction of two bodies .

As we know according to Newton's third law of motion , when the air rushes out and pushes against the air which pushes  the balloon to move in opposite direction , the action of the balloon pushes against the balloon moving it in the backward direction

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Answer:

At point A, the comet has the least kinetic energy because the comet is resting. 3. From point B to point D its orbit's potential energy is decreasing and its kinetic energy is increasing meaning it's moving more and more

Answer: C) the thickness of a sheet of paper.

Explanation:

A micrometer screw gauge is a tool that measures distances (in order of millimeters), from this, we can see that the correct option is C: the thickness of a sheet of paper.

Now let's expand on this.

Knowing that the micrometer only can measure distances, we need to analyze which of the options is only a distance.

Notice that while area and volume have similar units, are really different things.

So analyzing the options we have:

A) "the area of a sheet of paper"

To find the area we need two measures (length and width) and then multiply this, but with a micrometer, we never measure the length of a sheet of paper (the maximum measure that you can get in a micrometer is of a few centimeters).

B) "the mass of a sheet of paper"

We can't measure mass with a micrometer.

C) " the thickness of a sheet of paper"

The thickness of a sheet of paper is of the order of 1mm, so we can easily measure this with a micrometer screw gauge.

D) " the volume of a sheet of paper​"

We have a similar problem as the one seen in A.

Then the correct option is C.

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Answer:

I don't know what you mean about which changes occurred in this process but if its why the dough starts rising then its caused by the carbon dioxide in baking soda and yeast which is a fungus

Answer:

When baking,flour is mixed with water,the other ingredients and yeast to form a paste called a dough.what happens is that the zymase enzyme from the yeast acts on the sugars to form carbon dioxide and alcohol.the carbon dioxide begins to form bubbles in the dough causing it to rise..

I hope this helps

Answer:

they were in the sun for long

Answer:

.21

Explanation:

i see everyone got it wrong so ill give you the answer, good luck :)