Answer: they can not be replicated or repeated.
Explanation:
A historical events are opened for more study and research. So, they can be repeated for more study but with reference to the documents written about that event in a manner in which others are permitted to.
Where as, the conclusions related to historical events are limited to the subjective evaluation based on the different outcomes draw as a result of individual findings.
Which type of reaction happens when a base is mixed with an acid?
A.metal-base reaction
B.neutralization reaction
C.metal-acid reaction
D.spontaneous reaction
Answer:
Neutralization Reaction
Answer:
B
Explanation:
Usually, when a strong acid and a strong base is mixed together, the pH is neutralized, hence why it's called a neutralization reaction.
What must you do if you plan to exercise everyday
Answer: set up a reminder so you won't forget also try clearing your schedule so you can have more time
If a baseball is thrown straight up into the air, when does it have its greatest amount of gravitational potential energy?
Answer:
it has the highest potential energy when it is at the peak of it's height. why? cause PE = mgh where 'h' is the height. so PE will be maximum at max height!!
Answer:
It is when it is falling down it has its greatest amount of gravitational potential energy
Explanation:
This is because the gravitation of the earth pulls things closer to the earth
What is the frequency of UV light that has an energy of 2.39 × 10 -18 J?
Answer:
3.60 × [tex]10^{15}[/tex] Hz
Explanation:
[tex]\frac{2.39 * 10^{-18} J}{6.63 * 10^{-34} J.s}[/tex]
The frequency of UV light that has an energy of 2.39 × 10 -18 J is 3.60 × Hz.
What do you mean by frequency?The term frequency refers to the number of waves that pass a fixed point in unit time. It also describes the number of cycles or vibrations undergone during one unit of time by a body in periodic motion.
Moreover, frequency is the number of occurrences of a repeating event per unit of time. It is also occasionally referred to as temporal frequency for clarity, and is distinct from angular frequency. Frequency is measured in hertz which is equal to one event per second.
Therefore, the number of vibrations that a sound wave is making is called its frequency ( f ). Frequency can also be defined as the number of waves passing a given point in one second. Frequency is measured in hertz (Hz).
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What do magnets have the acts on a object without touching them?
1. A power
2. A force
3. A machine
4. A current
Need help ASAP
Answer: A force
Explanation:
Answer:
it's a force because magnetics can act on a object from a distance because of gravitational force
Explanation:
Why is tornadoes hitting the east coast of the USA?
Answer:
The outbreak of tornadoes that tore across the Gulf and the East Coast Tuesday and Wednesday was unusual for two reasons. For one thing, the severe weather encompassed a significant swath of the country. For another, winter is the least likely time for tornadic thunderstorms.
Explanation:
The outbreak of tornadoes that tore across the Gulf and the East Coast Tuesday and Wednesday was unusual for two reasons. For one thing, the severe weather encompassed a significant swath of the country. For another, winter is the least likely time for tornadic thunderstorms.
And yet tornadoes are an expected part of life in the United States—especially in the multi-state area known as Tornado Alley. (Florida, too, sees a disproportionately high number of tornadoes, because of its frequent thunderstorms.) The United States gets more tornadoes, by far, than any other place on the planet. It averages about 1,250 twisters a year. Canada, which sees about 100 tornadoes per year, is a “distant second,” according to the National Centers for Environmental Information.
what are examples of a medium?
A. water and air
B. amplitude and wavelength
C. crests and troughs
D. compressions and rarefactions
The Colorado Potato Beetle is one of the most important agricultural pests worldwide. How many pesticides has the Colorado Potato Beetle developed resistance to?
a
0
b
1
c
Less than 10
d
More than 50
Answer:
D - More than 50
Explanation:
Since the middle of the last century, the beetle has developed resistance to 52 different compounds belonging to all major insecticide classes.
Which term related to electromagnetism applies only to electric force?
A. Attraction
B. Noncontact
C. Repulsion
D. Charge
The charge applies only to the electric force.
Is charge directly related to electric force?Electrostatic force is directly related to the charge of each object. So if the charge of one object is doubled, then the force will become two times greater. Two times 0.080 N is 0.160 N.
Does the electric force only act on objects with charges?Electric forces can only act between charged objects - either like-charged or oppositely-charged. Electric forces between two charged objects increase with increasing separation distance.
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A hydrogen line in a star's spectrum has a frequency of 6.17*10^14 Hz when stationary. In Rigel's Spectrum, it is shifted downward by 4.26*10^10Hz. What is Rigel's velocity relative to us? m/s
Answer:
The correct answer will be "2.97 × 10⁸ m/s".
Explanation:
The give values are:
Observed frequency, [tex]F=4.26\times 10^{10} \ Hz[/tex]
Original frequency, [tex]F_{0}=6.17\times 10^{14} \ Hz[/tex]
Let the velocity of Rigel be = V m/s
As we know,
⇒ [tex]F_{0}=F\sqrt{\frac{C+V}{C-V}}\\[/tex]
On putting the values, we get
⇒ [tex]\frac{6.17\times 10^{14} }{4.26\times 10^{10} } =\sqrt{\frac{C+V}{C-V} }[/tex]
⇒ [tex]\frac{C+V}{C-V}=(14483.56808)^2[/tex]
⇒ [tex]\frac{C+V}{C-V}=209773744.2[/tex]
⇒ [tex]C+V=209773744.2 \ C-209773744.2 \ V[/tex]
⇒ [tex]C-209773744.2 \ C=209773744.2 \ V-V[/tex]
⇒ [tex]V=\frac{209773743.2}{209773745.2} \ C[/tex]
⇒ [tex]V=0.99 \ C[/tex]
So that the Rigel's velocity will be "0.99 C".
Now,
⇒ [tex]V=0.99\times 3\times 10^8[/tex]
⇒ [tex]=2.97\times 10^8 \ m/s[/tex]
What is the length of the x-component of the vector shown below?
A. 3.2
B.24.7
C. 2.8
D. 5.3
*
Answer:
D
Explanation:
Answer:
5.3
Explanation:
Just took the quiz
What is the motion of the particles in this kind of wave?
A hand holds the left end of a set of waves. The waves themselves make a larger set of waves in the same direction as that of the smaller waves. A label Wave motion is above the series of waves and an arrow next to the label points right.
A) The particles will move up and down over large areas.
B) The particles will move up and down over small areas.
C) The particles will move side to side over small areas.
D) The particles will move side to side over large areas.
Answer:
A
Explanation:
A because its in large areas and there all spread apart more and there all going up and down.
Determine the relationship between neutron stars and black holes
Answer:
When a dying star has a mass which is 1.4 to 3 times that of the sun, it will form a neutron star. Stars with a mass greater than thrice the sun's mass, black hole is formed.
Explanation:
1. How far can your little brother get if he can travel at 2.5 m/s and in 5 seconds
you will discover that his squirt gun has run out of paint?
12.5 m/s
12.5 m
025
2 m
Answer:
12.5 meters
Explanation:
what would be the effects of a baseball strike
Answer:
If you get 3 strikes in baseball your out and your batting Turn is Over
Explanation:
PLZ HELP
A wave has a wavelength of 4.9 m and a velocity of 9.8 m/s. The medium through which this wave is traveling is then heated so that the velocity is doubled.
If the frequency remains constant, what is the wavelength of the heated wave?
2.5 m
9.8 m
14.7 m
19.6 m
Answer: the wavelenght is 9.8 meters
Explanation:
We can use the relationship:
Velocity = wavelenght*frequency.
Initially we have:
wavelenght = 4.9m
velocity = 9.8m/s
then:
9.8m/s = 4.9m*f
f = 9.8m/s/4.9m = 2*1/s
now, if the velocity is doubled and the frequency remains the same, we have:
2*9.8m/s = wavelenght*2*1/s
wavelenght = (2*9.8m/s)*(1/2)s = 9.8 m
Answer:
B on Edge
Explanation:
Took the test
Which elements on the periodic table have the lowest electronegativity?
A. Elements on the bottom left
B. Elements on the bottom right
C. Elements on the top right
D. Elements on the top left
Answer: A
Elements on the bottom left
Explanation:
Electronegativity of an element increases across the group in a periodic table. And decreases across the period in a periodic table. That is
Group 7, the halogen family has the highest Electronegativity and period one in that group has the highest.
which statement about valence electrons is true?
A) they are located in the outer energy level of an atom
B) they are potentially involved in chemical reactions
C) they determine whether an element can conduct electricity
D) all of the above
Answer:
The correct answer is A
Answer:
They are the outer shell of an atom, So the most logical would be A.
Explanation:
According to a search i made a while ago about valence electrons, valence electron is an outer shell electron that is associated with an atom.
1. Although the sun is shining, it is a little chilly today at the beach. You look at your portable thermometer, which says it's 10°C. What is the temperature in Fahrenheit and Kelvin? Show the equations you use to make these conversions. (4 points)
Answer:
(10°C × 9/5) + 32 = 50°F
10°C + 273.15 = 283.15K
Explanation:
Someone help please please
Answer:
Air currents. etc
Explanation:
I think air currents formed near the equator have something to do with this the ocean also effects the weather with it's moisture you will have to put this in your own words.
A crane is used to lift an object. The crane applies a force of 400 to lift the object a distance of 25 meters in 20 seconds. Calculate the work in J performed by the crane to lift the object
Answer:
400*25
W = 10000 J
Explanation:
I believe time is irrelevant in work although it is important in the formula for power.
You are kicking your soccer ball back and forth on a soccer field. You kick the ball forward for 10 m. You turn completely around and kick the ball back for 20 m. Your turn again and kick the ball forward for 40 m. What is your distance and what is your displacedment?
Answer:
1.) Total distance = 70 m
2.) Total displacement = +30m
Explanation:
Distance is a scaler quantity. That is, we will be concerned about its magnitude only and not direction.
Total distance = 10 + 20 + 40 = 70 m
While displacement is a vector quantity. We will consider both the magnitude and its direction.
Forward direction will be positive while backward direction will be negative
Total displacement = +10 - 20 + 40
Total displacement = +30 m
In a transistor, collector current is controlled by
Base
Collector
Emitter
Answer:
Collector current is controlled by the Base current.
In a transistor collector current is controlled by: Base current ( A )
What is a transistor ?A transistor is an electrical device ( semi conductor ) which is used to switch off or on electrical signals and power. It can also amplify electrical signals and power. The collector current in a transistor is called by the base current when the transistor is in its active region.
Hence we can conclude that In a transistor collector current is controlled by: Base current ( A ) .
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A stone is dropped from a 75-m- high building . When this stone has dropped 15 m, a second stone is thrown downward with an initial velocity such that the two stones hit the ground at the same time. What was the initial velocity of the second stone?
Answer:
The initial velocity of the second stone is 34.3 m/s
Explanation:
The distance height covered by the second stone will be
75m - 15m = 60 m
Since the two stones hit the ground at the same time.
Using third equation of motion, which state that;
V^2 = U^2 - 2gH
Where
U = Initial velocity
V = final velocity
H = 60 m
g = 9.81 m/s^2
As the stone reaching the ground, that is, coming to rest, V = 0. Therefore,
Substitute all the parameters into the equation
0 = U^2 - 2 × 9.81 × 60
U^2 = 1177.2
U = 34.3 m/s
The initial velocity of the second stone is 34.3 m/s
Can anyone help me assssssaaaaaaaappppp
Answer: Heat Cramps
Explanation:
Sunburn isn't caused by sweating. When one has heat stroke, they do not sweat. Heat cramps are a SYMPTOM of heat cramps, but heat exhaustion includes much more than just heat cramps.
Oxygen and other nonmetals are found in which area of the periodic table?
on the left side
on the right side
in the bottom two rows
in the middle section
Answer:upper right hand side i think
Explanation:
A tuba creates a 4th Harmonic of frequency 116.5 Hz. When the first valve is pushed, it opens an extra bit of tubing 0.721m long. What is the new frequency of the 4th Harmonic? Hz
Answer: New frequency = 103.3Hz
Explanation:
Given that the
Frequency F = 116.5 Hz
The tube is an opened tube.
The relationship between wavelength and the length of the tube is
λ = 2L/n
Where
λ = wavelength
L = length of the tube
n = number of harmonic
For 4th harmonic,
λ = 2L/4 = L/2
But wave speed V = F(λ)
Substitutes (λ) into the wave speed formula
V = FL/2
Let's assume that the V is the speed of sound = 330m/s
Substitutes the V and F into the formula above.
330 = 116.5L/2
Cross multiply
660 = 116.5L
L = 660/116.5
L = 5.67 m
Given that the first valve is pushed, it opens an extra bit of tubing 0.721m long.
New length = 5.67 + 0.721 = 6.39 m
New frequency will be
330 = 6.39F/2
Cross multiply
660 = 6.39F
F = 660/6.39
F = 103.3 Hz
PLEASE HELP!!
Calculate the transfer of energy by a force of 15N when it movies the object by a distance of 5 m
a. In the direction of the force
b. In the direction at 60 degrees to the direction of the force
c. At right angles to the force
Answer:
a. 75 joules
b. 37.5 joules
c. 0 joules
Explanation:
work is defined as the product of force times the distance moved in the direction of the force
Given data
force F= 15N
distance S= 5m
In the direction of the force[tex]force= 15*5\\force= 75 joules[/tex]
2. In the direction at 60 degrees to the direction of the force
[tex]force= 15cos 60* 5\\force= 15*0.5*5\\force= 37.5 joules[/tex]
3. At right angles to the force
[tex]force= 15cos 90* 5\\force= 15*0*5\\force= 0 joules[/tex]
Why is air considered a fluid
Answer:
A fluids is any substance that flows. Air is made of stuff, air particles, that are loosely held together in a gas form. Although liquids are the most commonly recognized fluids, gasses are also fluids. Since air is a gas, it flows and takes the form of its container.
Explanation:
Because it possesses the essential characteristics of fluids, air is regarded as a fluid.
A substance that may flow and take on the shape of its container is called a fluid. Here are several explanations for why air is seen as a liquid:
Air has the ability to flow and move freely. It can easily alter its location or direction of movement because it is neither hard nor fixed in shape.Air is fluid, allowing air molecules to readily flow past one another.Compressibility: Pressure-induced compression or expansion of air is possible. Air, like other fluids, has a property known as buoyancy that allows it to pull upward.Thus given these qualities, air satisfies the requirements for fluidity and is frequently categorised as such in the study of fluid mechanics.
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PLLSSSS HELP
MARKING BRAINLIST
SCIENCE
Answer:
the first one
Explanation: the first one because they were all on two different continents so when they seperated half of the species went on one continent and the other half went onto another one