The answer is C :), I think.
A scientific paper is the primary source. A primary source is an item, document, recording, or any other source. Option C is correct.
What is a scientific paper ?Scientific papers are a specific sort of written work with certain characteristics: they are often published in a periodical called a journal, whose sole objective is to publish this type of work.
A primary source is an item, document, recording, or any other source of information created during the period being studied in the academic area of history.
A scientific paper is the primary source.
Hence,option C is correct.
To learn more about the scientific paper, refer:
https://brainly.com/question/1716162
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one car accelerates at half the rate of another how much longer does it take the first car to travel a quarter mile
Answer:
t=1/4v1
Explanation:
Given data
Car one
Speed =v1
Time =t
Distance =1/4 mile
Given data
Car two
Speed =v1/2
Time =t
Distance =d
Speed =distance/time
v1=1/4/t
v1t=1/4
t=1/4*1/v1
t=1/4v1 seconds
What happens in a series circuit when more bulbs are added? (Example: I start out with a complete series circuit with 2 bulbs. Then I add in several more wires and several more bulbs & bulb holders. Now I have a complete series circuit with 5 bulbs).
Answer:
when we add elements in a series circuit the voltage across each element decreases
Explanation:
In a series circuit the current the whole circuit is the same, since there is only one path,
resistance is the sum of the resistance of each element
R_{eq} = ∑ R_i
if we write ohm's law
V = i R_{eq}
we substitute
V = i ∑ R_i
therefore the total voltage is
V = ∑ i R_i = ∑ V_i
With this expression we see that the voltage decreases as we place more elements in the series circuit.
Specifically when we fear two elements the voltage across each element is
V_i = V / 2
when we have 5 elements the voltage across each element is
V_i = V / 5
therefore when we add elements in a series circuit the voltage across each element decreases
1) Convert the following:
I) 65 kg into g
ii) 87570 seconds into hour
iii) 7.5 km into m
Answer:
65000g
24.325 hrs
7500m
Answer:
I) 65000 g II)24.325 hours III)7500 m
Explanation:
I) 1 kg = 1000 g
65 kg = 65 * 1000 g = 65000 g
II) 1 hour = 3600 seconds
1 second = 1/3600 hours
87570 seconds = 87570 * 1/3600 hours =24.325 hours
III) 1 km = 1000 m
7.5 km = 7.5 * 1000 m = 7500 m
Astronomers observe the Small Magellanic Cloud (SMC), a not very dense, rather small galaxy near us. They notice that even those stars that formed recently have relatively few heavier elements (when compared to such recent stars in our Milky Way.) What is the likely explanation for this deficiency
Answer:
The reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.
Explanation:
The Small Magellanic Cloud, is basically a very tiny galaxy located near the Milky Way. Although it's tiny, it's diameter is approximately 7,000 light-years while it also contains over hundred million stars which are widely spaced.
Now, the reason it has few heavier elements is due to the fact that it's stars are widely spaced and this implies that it's stars have very low rate of formation and termination.
To leave the gravitational pull of the Earth, and explore other planets, satellites must have at least:
Answer:
To explore the other planets, the satellite must have the velocity more than the escape velocity.
Explanation:
The minimum velocity required by any object to escape from the earth gravitational pull is called the escape velocity.
The escape velocity for any planet depends on the mass of planet and radius of planet. It does not depends on the mass of object. The escape velocity is same for any mass for a particular planet.
So, to explore the other planets, the satellite must have the velocity more than the escape velocity.
A uniform metre ruler scale balanced at 40 cm mark, when weight 25 gf and 10gf are suspended at 10cm mark and 75 cm mark respectively.Calculate the weight of the metre scale.
Answer:
40 gf.
Explanation:
Please see attached photo for diagram.
In the attached photo, W is the weight of metre rule.
The weight of the metre rule can be obtained as follow:
Clockwise moment = (W×10) + (10×35)
Clockwise moment = 10W + 350
Anticlock wise moment = 25 × 30
Anticlock wise moment = 750
Clockwise moment = Anticlock wise moment
10W + 350 = 750
Collect like terms
10W = 750 – 370
10W = 400
Divide both side by 10
W = 400/ 10
W = 40 gf
Thus, the weight of the metre rule is 40 gf
Answer:
40 gf
Explanation:
The balance point of the uniform meter rule with the suspended weights = 40 cm = The pivot point
The location where the 25 gf weight is suspended = 10 cm
The location where the 10 gf weight is suspended = 75 cm
Let W represent the weight of the meter rule.
We have that the location of the application of the weight of the meter rule is at the center, 50 cm mark, point
Given that the meter rule is balanced, and taking moment about the pivot point, we have;
The moment om the left hand side, LHS, of the pivot point = The moment on the right hand side, RHS, of the pivot point
The moment on the LHS = 25 gf × (40 cm - 10 cm) = 750 gf·cm
The moment on the RHS = W × (50 cm - 40 cm) + 10 gf × (75 cm - 40 cm)
The moment on the RHS = W·(10 cm) + 350 gf·cm
∴ 750 gf·cm = W·(10 cm) + 350 gf·cm
W·(10 cm) = 750 gf·cm - 350 gf·cm = 400 gf·cm
W = (400 gf·cm)/(10 cm) = 40 gf
The weight of the meter scale (rule), W = 40 gf.
help me daddyz Alice did an experiment to find the relationship between the angle at which a ray of light strikes a mirror and the angle at which the mirror reflects the light. She placed a ray box in front of a mirror. She changed the angle at which the light from the ray box struck the mirror and noted the corresponding angle at which the mirror reflected the light. Which of the following is the control variable in this experiment? The ray box used as the source of light The direction along which the light moves Angle at which the light from the ray box strikes the mirror Angle at which the mirror reflects the light from the ray box
Answer:
The ray box used as the source of light
Answer: its A
Explanation: i just did the test and got it right also known. The ray used as the source of light
Each tire on a car has a radius of 0.330 m and is rotating with an angular speed of 11.7 revolutions/s. Find the linear speed v of the car, assuming that the tires are not slipping against the ground. v
Answer:
The linear speed of the car, v, is 24.26 m/s
Explanation:
Given;
radius of the car's tire, r = 0.330 m
angular speed of the car, ω = 11.7 revolutions/s
The angular speed of the car in radian per second:
[tex]\omega = 11.7 \ \frac{rev}{s} \times \frac{2\pi \ rad}{1 \ rev} \\\\\omega = 73.523 \ rad/s[/tex]
The linear speed of the car, v, is calculated as;
v = ωr
v = 73.523 rad/s x 0.33 m
v = 24.26 m/s
Therefore, the linear speed of the car, v, is 24.26 m/s
Ehy Newton's law of gravitation also called universal law?
Answer:
Gravity is a natural phenomenon that causes all massive objects to attract each other. The magnitude or force of this interaction depends on the masses and distance of the bodies. This causes objects to fall toward Earth, for example, and keep satellites and celestial bodies in their orbits, such as the Earth's orbit around the Sun. Gravity also causes the tidal phenomenon.
In physics, gravity can be approximated by Isaac Newton's laws of gravity. Although the accuracy of the law is sufficient, for example, when calculating the orbits of spacecraft, gravity is best described by Albert Einstein’s general theory of relativity, in which it is considered the curvature of space-time.
When an apple falls towards the earth, the earth moves up to meet the apple . Is this true ? If yes . Why is the earth's motion not noticeable.
A 90 kg astronaut Travis is stranded in space at a point 12 m from his spaceship. In order to get back to his ship, Travis throws a 0.50 kg piece of equipment so that it moves at a speed of 4 m/ s directly away from the spaceship towards the left . How long will it take him to reach the ship? *hint find his speed after the collision and consider it a constant speed all the way back to his spaceship*
Answer:
Explanation:
This is a recoil problem, which is just another application of the Law of Momentum Conservation. The equation for us is:
[tex][m_av_a+m_ev_e]_b=[m_av_a+m_ev_e]_a[/tex] which, in words, is
The momentum of the astronaut plus the momentum of the piece of equipment before the equipment is thrown has to be equal to the momentum of all that same stuff after the equipment is thrown. Filling in:
[tex][(90.0)(0)+(.50)(0)]_b=[(90.0)(v)+(.50)(-4.0)]_a[/tex]
Obviously, on the left side of the equation, nothing is moving so the whole left side equals 0. Doing the math on the right and paying specific attention to the sig fig's here (notice, I added a 0 after the 4 in the velocity value so our sig fig's are 2 instead of just 1. 1 is useless in most applications).
0 = 90.0v - 2.0 and
2.0 = 90.0v so
v = .022 m/s This is the rate at which he is moving TOWARDS the ship (negative was moving away from the ship, as indicated by the - in the problem). Now we can use the d = rt equation to find out how long this process will take him if he wants to reach his ship before he dies.
12 = .022t and
t = 550 seconds, which is the same thing as 9.2 minutes
In the diagram, q1 = +2.00 x 10-5 C,
q2 = +3.80 x 10-6 C, and q3 = +5.30 x 10-5 C.
What is the electric potential energy, Ue, for
charge qy? Include the correct sign (+ or -).
Answer:
U = 3.59 10⁻⁹ J
Explanation:
Electric potential energy is
U = k ∑ [tex]\frac{q_iq_j }{r_i_j}[/tex]
in this case
U = k (q₁q₂ / r₁₂ + q₁q₃ / r₁₃ + q₂q₃ / r₂₃)
the distances are
r₁₂ = 1.15
r₁₃ = 1.15 +2.88 = 4.03 m
r₂₃23 = 2.88
we substitute
U = 9 109 (2 10-5 3.8 10-6 / 1.15 + 2 10-5 5.30 10-5 / 4.03 + 3.8010-6 53 010-5 / 2.88)
U = 9 109 (6.609 10-11 + 2.63 10-10 + 6.99 10-11)
U = 9 109 (39,899 10-11)
U = 3.59 10⁻⁹ J
Answer:
Q2 = 0.0346 J
Explanation:
I don't know what Q1 is but I did solve for Q2. I'm using this because no other question has been asked to solve for Q2 :)
Space weather is dominated by a stream of charged particles emanating from the sun's magnetic field, known as ______________.
Answer:
solar windExplanation:
This stream of particles emanating from sun's magnetic field is known as the solar wind.
The gas and particles come from the Sun's hot outer atmosphere, called the corona. These particles from the corona are charged with electricity.
TRUE OR FALSE. when an object changed direction without changing its speed, it is not accelerating
Answer:
True.
Explanation:
The velocity vector is constant in magnitude but changing in direction. Because the speed is constant for such a motion, many students have the misconception that there is no acceleration. ... But the fact is that an accelerating object is an object that is changing its velocity.
If voltage , V = 100 + 6 volt and current , I = 10+ 0.2 A , then find
percentage error in R.
Explanation:
As we know, resistance is the ratio of voltage used and current flowing through the circuit. So,
R = V/IBy error calculation
∆R/R = [(∆V/V)100] + [(∆I/I)100]V = 100 ± 6% V
I = 10 ± 0.2% A
∆R/R= (5/100)×100 + (0.2/10)×100
∆R/R=5+2=7%
So, percentage error in resistance (R) = ± 7%.Answer:
Percentage error of R is ±7%
3.00 m^3 of water is at 20.0°C.
If you raise its temperature to
60.0°C, by how much will its
volume expand?
Water
ß = 207•10-6C-1
(Unit = m^3)
Answer:
9m^3
Explanation:
Given data
volume v1= 3m^3
volume v2= ???
Temperature T1= 20.0°C.
Temperature T2= 60.0°C.
Applying the relation for temperature and volume
V1/T1= V2/T2
substitute
3/20= V2/60
3*60= V2*20
180= 20*V2
180/20= V2
V2= 9m^3
Hence the final volume is 9m^3
An acceptable radiograph was taken using 40 mAs at 80 kVp at a distance of 60 inches. A second radiograph is requested at 40 inches. What mAs should be used to produce this radiograph with a 40-inch distance
Answer:
17.8 mAs
Explanation:
The exposure maintenance formula shows that as SID increases, intensity decreases, causing a decrease in film exposure and density. The mAs is directly proportional to the square of the distance. That is as mAs increases, distance increases, and vice versa, in order to maintain image receptor exposure. It is given by:
[tex]\frac{mAs_1}{mAs_2}=\frac{D_1^2}{D_2^2}[/tex]
Given that mAs₁ = original mAs = 40 mAs, D₁ original distance = 60 in, D₂ = new distance = 40 in, mAs₂ = new mAs
[tex]\frac{mAs_1}{mAs_2}=\frac{D_1^2}{D_2^2}\\\\mAs_2=\frac{mAs_1*D_2^2}{D_1^2}=\frac{40*40^2}{60^2}=17.8\\\\mAs_2=17.8\ mAs[/tex]
what is the closest to the order of magnitude of the energy rquired to split a nucleus in to its individual protons and neutrons
Answer:
More than two million electron volts.
Explanation:
More than two million electron volts energy are needed to break or split a deuteron into a proton and a neutron. Nuclear binding energy is the type of energy that is required to split an atom's nucleus into protons and neutrons. The deuteron is an isotope of hydrogen that is composed of a proton and a neutron and it is a stable particle. Very huge amount of energy is needed for the splitting of nucleus due to the presence of heavy particles i.e. proton and neutron.
Which of the following is an example of a surface wave?
A. Compression wave
B. Sound wave
C. Electromagnetic wave
D. Ocean wave
Answer:
ocean wave
hope it helped you
Velocity is vector quantity because??
Velocity is vector quantity because it has both magnitude and direction.
Explanation:
velocity is a vector quantity because the person always returns to the original position,the motion would never result in a change in a position.
what is good operating practice concerning the use of aircraft lighting while on the ground at night
Answer:
It is important to be extra careful at night and in periods of low visibility from sunset to sunrise and to focus on operating the aircraft safely when the aircraft is moving. Ensure checklist are run through and avoid non essential communications prior to the aircraft being stopped and the breaks are set
Explanation:
According to aircraft rules and regulation, the position lights of an aircraft are required to be switched on on an aircraft which is either operated on the surface and during flight from sunset to sunrise or when the elevation of the Sun below the horizon is more than 6°
However, the anti collision lights are not required to be lighted during night operations, unless the pilot in command specifies it for safety reasons
Which statement or question is a good hypothesis
A ball is dropped from a roof of a building and strikes the ground in 3 seconds. If a second ball is thrown horizontally from the roof, it will hit the ground in:
it will hit the ground maybe in like 1 second I guess
Name One formula that uses joules
Answer:
[tex]{ \bf{power \: { \tt{(watts)}} = \frac{workdone \: { \tt{(joules)}}}{time \: { \tt{(seconds)}}} \: }}[/tex]
for the equation BaCI2 + Na2SO4 > BaSO4 + 2NaCI
A. reactants: 1 ;products: 1
B. reactants: 1 ;products: 2
C. reactants: 2 ;products: 1
D. reactants: 2 ;products: 2
a car is travelling at 36 km per hour if its velocity increases to 72 km per hour in 5 seconds then find the acceleration of car in SI unit
Answer:
36 km /h means 10 m/s. Increase in speed is 10m/s in 5 s . Acceleration is ( 10/5 ) = 2 m/s^ 2.
a= 2m/s²
Explanation:
U=36km/h
V=72km/h
T=5s
Conversion of Km to m and H to s
1km = 1000m
36km=36×1000 = 36000m
1H = 3600s
For U, 36000/3600
=10m/s
For V,
72km= 72×1000 =72000
72000/3600
20m/s
a=(V-U)/T
a=(20-10)/5
a= 10/5
a= 2m/s²
Hallar la distancia que recorre una movil al cabo
de 8s si posee una velocidad de 5m/s y acelera a razón de 3 m/s
Answer:
Distancia, S = 136 metros
Explanation:
Dados los siguientes datos;
Aceleración, a = 3 m/s²
Velocidad inicial, u = 5 m/s
Tiempo, t = 8 segundos
Para encontrar la distancia recorrida, usaríamos la segunda ecuación de movimiento;
S = ut + ½at² Sustituyendo en la fórmula, tenemos;
S = 5 × 8 + ½ × 3 × 8²
S = 40 + 1,5 × 64
S = 40 + 96
Distancia, S = 136 metros
what is kepler's law??
➜what is kepler's law??
[tex]\huge\red{\boxed{\huge\mathbb{\red A \pink{N}\purple{S} \blue{W}\orange{ER}}}}[/tex]
Kepler gave the three laws or theorems of motion of the orbitals bodies
[tex]{\huge {\bold{ \red{ \star}}}}{ \blue{ \bold{FIRST \: \: \: LAW}}}[/tex]
This law state that the celestial bodies revolves around the stars in elliptical orbit and star as a single focus.
Example :- Earth revolves around the Sun as assuming it as single focus
This also shows that earth revolves around the sun in elliptical orbit.
[tex]{\huge {\bold{ \blue{ \star}}}}{ \green{ \bold{SECOND \: \: \: LAW}}}[/tex]
Area covered by the planet is equal in equal duration of time irrespective of the position of the planet.
It also states that Angular momentum is constant
As Angular momentum is constant it means areal velocity is also constant.
[tex]\frac{ \triangle \: A}{ \triangle \: T} = \frac{L}{2m}△T△A=2mL[/tex]
where:-
A is the area.
T is the time.
L is the angular momentum.
M is the mass of the body.
[tex]{\huge {\bold{ \green{ \star}}}}{ \purple{ \bold{THIRD \: \: \: LAW}}}[/tex]
square of the time of the revolution is directly proportional to the cube of the distance between the planet and star in Astronomical unit.
[tex]{T}^{2} = {a}^{3}T2=a3[/tex]
where:-
T = time of revolution
a is the distance between the planet and star.
[tex]\purple\star \: {Thanks \: And \: Brainlist} \blue \star \\ {\orange{ \star}}{if \: U \: Like d \: My \: Ans} {\green{ \star }}[/tex]
If displacement has a magnitude AND direction is it a scalar or vector quantity?
scalar
vector
Explanation:
Obviously vector quantity
Using atomic weight crystal structure and atomic radius data tabulated inside the front cover compute the theoritical densities of alminuim ,nikel......
Question
Using atomic weight, crystal structure, and atomic radius data tabulated inside the front cover of thebook, compute the theoretical densities of aluminum (Al), nickel (Ni), magnesium (Mg), and tungsten (W), and thencompare these values with the measured densities listed in this same table. The c/a ratio for magnesium is 1.624.
Explanation: