The II next to elements represent the number of atoms which are joined together for forming a molecule.
The Roman numeral (II) if written next to an element then it denotes the oxidation state of the ion.
Let us assume that,
We need to represent the two atoms of an element Nitrogen, we can either denote it by writing NN or we can simply write N2.
Here 2 which is written in the subscript of an atoms denotes that for forming N2 two atoms of Nitrogens are used.
In some places, Roman numerals are also used.
In Chemistry Roman numerals like (I, II. III etc) are used for denoting the charge and the oxidation state of the transition metal ion.
Some common examples are Fe2+ and Fe3+.
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Calculate the charge if one miliAmp flows for 1 second
Answer:
Thus 1 Ampere is the current is defined as flow of 1 coulomb charge through a conductor in 1 second.
Explanation:
Hope it helps
Which statement best summarizes the development of the atomic theory over time?
Answer:
electrons move around nucleus in specific regions
We have that the correct statement that summarizes atoms over time will be
The discovery of new evidence resulted in changes to the atomic theory.
Option B
Generally
The Image shows that in the early 1800 the knowledge of atom was limited and it increased over time and by 1920 it had gone through a 4 stages of modifications to the atomic model
Atoms are solid spheresElectrons are attached to atom surfaceElectrons move around in the nucleus in a specificRapid motion of electrons in the cloudTherefore the correct statement that summarizes atoms over time will be
The discovery of new evidence resulted in changes to the atomic theory
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In which reaction are the atoms of elements rearranged?
Milk is a very weak acid. What might its pH value be ?
Answer:
pH value is between 6.5 and 6.8
Explanation:
Explanation:
Milk fresh from the cow typically has a pH between 6.5 and 6.7. The pH of milk changes over
Hello I need help with my science HW
Did you see a pattern in the ratios between mass and weight? Explain what you think this pattern means.
Answer:
please put a picture, i dont know what you are doing so i cant help.
Explanation:
What must happen to light in order for an image to form
Imagine you leave the dock on a fishing boat that travels east for 30 kilometers when the captain realizes he left the fishing rods on the dock. It takes him 40 minutes to travel out against the current but only 20 minutes to return to the dock.
Answer:
Average speed is 60 km/hr whereas average velocity is 0 km/ hr.
Explanation:
The average speed of the boat is 60 km/ hr while on the other hand, the average velocity of the boat is 0 km/ hr because average speed is the total distance covered by the boat in total time and average velocity is the displacement covered by the boat in total time. The total distance covered by the boat is 60 km and the total time is 60 minutes which is equals to one hour so the answer is 60 km/hr whereas the displacement is the shortest distance between initial and final position which is 0 in this case so 0 divided by 60 minutes or one hour is also 0.
A physics student of mass 43.0 kg is standing at the edge of the flat roof of a building, 12.0 m above the sidewalk. An unfriendly dog is running across the roof toward her. Next to her is a large wheel mounted on a horizontal axle at its center. The wheel, used to lift objects from the ground to the roof, has a light crank attached to it and a light rope wrapped around it; the free end of the rope hangs over the edge of the roof. The student radius 0.300 m and a moment of inertia of 9.60 kg m^2 for rotation about the axle, how long does it take her to reach the side walk, and how fast will she be moving just beofre she lands?
Answer:
The speed of the student just before she lands, v₂ is approximately 8.225 m/s
Explanation:
The given parameters are;
The mass of the physic student, m = 43.0 kg
The height at which the student is standing, h = 12.0 m
The radius of the wheel, r = 0.300 m
The moment of inertia of the wheel, I = 9.60 kg·m²
The initial potential energy of the female student, P.E.₁ = m·g·h₁
Where;
m = 43.0 kg
g = The acceleration due to gravity ≈ 9.81 m/s²
h = 12.0 h
∴ P.E.₁ = 43 kg × 9.81 m/s² × 12.0 m = 5061.96 J
The kinetic rotational energy of the wheel and kinetic energy of the student supporting herself from the rope she grabs and steps off the roof, K₁, is given as follows;
[tex]K_1 = \dfrac{1}{2} \cdot m \cdot v_{1}^2+\dfrac{1}{2} \cdot I \cdot \omega_{1}^2[/tex]
The initial kinetic energy, 1/2·m·v₁² and the initial kinetic rotational energy, 1/2·m·ω₁² are 0
∴ K₁ = 0 + 0 = 0
The final potential energy of the student when lands. P.E.₂ = m·g·h₂ = 0
Where;
h₂ = 0 m
The final kinetic energy, K₂, of the wheel and student is give as follows;
[tex]K_2 = \dfrac{1}{2} \cdot m \cdot v_{2}^2+\dfrac{1}{2} \cdot I \cdot \omega_{2}^2[/tex]
Where;
v₂ = The speed of the student just before she lands
ω₂ = The angular velocity of the wheel just before she lands
By the conservation of energy, we have;
P.E.₁ + K₁ = P.E.₂ + K₂
∴ m·g·h₁ + [tex]\dfrac{1}{2} \cdot m \cdot v_{1}^2+\dfrac{1}{2} \cdot I \cdot \omega_{1}^2[/tex] = m·g·h₂ + [tex]\dfrac{1}{2} \cdot m \cdot v_{2}^2+\dfrac{1}{2} \cdot I \cdot \omega_{2}^2[/tex]
Where;
ω₂ = v₂/r
∴ 5061.96 J + 0 = 0 + [tex]\dfrac{1}{2} \times 43.0 \, kg \times v_{2}^2+\dfrac{1}{2} \times 9.60 \, kg\cdot m^2 \cdot \left (\dfrac{v_2}{0.300 \, m} }\right ) ^2[/tex]
5,061.96 J = 21.5 kg × v₂² + 53.[tex]\overline 3[/tex] kg × v₂² = 21.5 kg × v₂² + 160/3 kg × v₂²
v₂² = 5,061.96 J/(21.5 kg + 160/3 kg) ≈ 67.643118 m²/s²
v₂ ≈ √(67.643118 m²/s²) ≈ 8.22454363 m/s
The speed of the student just before she lands, v₂ ≈ 8.225 m/s.
When light passes from air into water at an angle of 60° from the normal, what is the angle of refraction? (40.6°)
Answer:
40.6°
Explanation:
The angle of refraction, when light passes from air into water at an angle of 60° from the normal, is 40.6°
What is Snell's law?It states that the ratio of sine of angle of incidence and angle of refraction is equal to the refractive index of second medium to the first medium.
sini/sinr =n₂ / n₁
Given, the light passes from air into water at an angle of 60° from the normal, the angle of incidence i = 60°, refractive index of air n₁ =1, refractive index of water n₂ = 1.333, then the angle of refraction is
sinr = sini x (n₁/n₂)
Plug the values, we get
sinr = sin60 x (1/1.333)
sinr = 40.6°
The angle of refraction is less than angle of incidence due to refraction.
Thus, the angle of refraction is 40.6°
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How does friction affect the output of machines?
Answer:
In a machine, friction reduces the mechanical advantage, or the ratio of output to input: an automobile, for instance, uses one-quarter of its energy on reducing friction. Yet, it is also friction in the tires that allows the car to stay on the road, and friction in the clutch that makes it possible to drive at all
Explanation:
hope it will help you
A firework is launched with a force of 700 N and a momentum of 200 kg-m/s. How much time before is explodes?
Answer:
t = 0.28 seconds
Explanation:
Given that,
Force acting on a firework, F = 700 N
The momentum of the firework, p =200 kg-m/s
We need to find the time before it explodes. Ket the time be t. We know that, the rate of change of momentum is equal to external frce. So,
[tex]F=\dfrac{P}{t}\\\\t=\dfrac{P}{F}\\\\t=\dfrac{200}{700}\\t=0.28\ s[/tex]
So, the required time is equal to 0.28 seconds.
xplain the difference between aerobic and anaerobic exercise and give 1 example of each?
Answer:
The term "aerobic" refers to the body's ability to provide energy through the use of oxygen. The term anaerobic refers to the body's ability to provide energy without the use of oxygen.
An example of an aerobic exercise is swimming. An example of an anaerobic exercise is sprinting.
Explanation:
Answer:
An example of an aerobic exercise is swimming. An example of an anaerobic exercise is sprinting.
Explanation:
A 1.70 m long string has a standing wave with 2 loops at a frequency of 38.4 Hz. What is the speed of the waves in the string? (Unit = m/s)
Answer:65.28
Explanation:
A long string has a standing wave with 2 loops at a frequency. The speed of the waves in the string is 65.28 m/s
What is frequency?The frequency is the number of cycles completed per second.
Given the length of the string l = is 1.70 m, no of loops n =2, frequency of wave f =38.4 Hz, then the speed of the waves is
f = nv /2l
Substitute the following values, we get
v = 38.4 x 2 x 1.70 / 2
v =65.28 m/s
Thus, the speed of the waves in the string is 65.28 m/s.
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John, a fireman, slides down a pole when the fire alarm sounds. He reaches the ground at 5m^-1. Give that his mass is 60kg. Find the friction that acts against his motion as he slides down the pole.
The tendency to pull other objects toward it is called
Answer:
""gravity. the force that pulls on objects and causes acceleration if the objects are not balanced by an opposing force. speed. distance traveled per unit time. Newton's Second Law of Motion.""
Explanation:
PLEASE ANSWER THIS ASAP I WILL MARK YOU THE BRAINLIEST The actual subject is Science but they dont have that as a option in pick a subject
Answer:
Sam's average velocity for the entire walk is approximately;
0.075 km/min
Explanation:
The given parameters of the Lake Loop Trail are;
The distance of the trail Sam takes his dog to walk around = 5-km
From the table for the position and time, we have;
[tex]\begin{array}{ccc}Position \ (km) &&Time \ (min)\\0&&0\\1&&12\\2&&22\\3&&33\\4&&54\\5&&67\end{array}[/tex]
Plotting the given points gives the attached chart created with Microsoft Excel
The coordinates of the points are A(0,0), B(67, 5), C(67, 0)
By the definition of average velocity, we have;
[tex]Average \ velocity = \dfrac{Total \ distance}{Total \ time \ taken}[/tex]
From the plot of the points therefore, we have;
[tex]Average \ velocity= \dfrac{Length \ of BC}{The \ time \ elapsed \ between \ AC} = \dfrac{5 \ km - 0 \ km}{67 \ min - 0 \ min} = \dfrac{5 \ km}{67 \ min} \approx 0.075 \ km/min[/tex]Therefore;
Sam walked at an average velocity of approximately 0.075 km/min.
When two chemical atoms form a chemical bond, the expected result is that the electrons
A.)will be in the excited state
B.) will be equal to the number of protons
C.) will complete a noble gas configuration in both atoms
D.) will be removed completely from both atoms
Answer:
B
Explanation:
atoms with equal or similar electronegativity form covalent bonds in which the valence electrons are shared between the two atom
During the formation of a chemical bond, the expected result is that the electrons will complete a noble gas configuration in both atoms. Hence, option (C) is correct.
The given problem is based on the concepts and fundamentals of chemical bonds. The chemical bonds between the two atomic species is formed by sharing the electrons.
When the electrons from each of the atom is shared, they maintain a strong intermolecular bond, which is known as chemical bond. This chemical bond allows the element to achieve noble gas configuration.The electrons that is shared within the two atomic species are known as shared pairs.The shared pairs are bonded within the atomic species by means of Van der Waals force of attraction as as covalent interaction..Thus, we can conclude that during the formation of a chemical bond, the expected result is that the electrons will complete a noble gas configuration in both atoms. Hence, option (C) is correct.
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3. Neha travels 4 m towards the north, 3m towards the east, and then 7 m towards south, find the displacement and total distance traveled by her.
Answer:
Explanation:
Explanation: total displacement =3√2m. and total distance covered=14m. I hope this is right and helps u.
Please help please real quick
Answer:
1. (a) The final velocity is 20 m/s
(b) The distance travelled is20 meters
2. The distance travelled by the train in the 30 seconds is 825 meters
3. The most correct option is;
(d) 53 km
4. The heat, developed by the electric iron is 15,000 joules
5. a) In the first network the resistance between A and B is 2 Ω
b) In the second network the resistance between A and B is 4Ω
c) In the third network the resistance between A and B is 6Ω
d) In the fourth network the resistance between A and B is 2Ω
Explanation:
1. (a) The parameters of the cheetahs motion are;
The initial motion (velocity) of the cheetah = 0 m/s (The cheetah starts from rest)
The acceleration of the cheetah, a = 2 m/s²
The duration of the acceleration of the cheetah, t = 10 seconds
The kinematic equation of the motion of uniform acceleration, of the cheetah can be written in the following form;
v = u + a·t
s = u·t + 1/2·a·t²
Where;
v = The final velocity
u = The initial velocity = 0 m/s
a = The acceleration of the cheetah = 2 m/s²
s = The distance traveled
∴ v = 0 + 2 × 10 = 20
The final velocity, v = 20 m/s
(b) From s = u·t + 1/2·a·t², we have;
s = 0 × 10 + 1/2 × 10 × 2² = 20
The distance travelled, s = 20 meters
2. The given details of the motion of the train are;
The initial velocity of the train, u = 20 m·s⁻¹
The acceleration of the train, a = 0.5 m·s⁻²
The duration of the train's acceleration, t = 30 seconds
Therefore, the distance travelled, 's', is given by; s = u·t + 1/2·a·t²
∴ s = 20 × 30 + (1/2) × 0.5 × 30² = 825
The distance travelled by the train in the 30 seconds, s = 825 meters
3. The given distance the truck covers with the average speed of 80 km/h, d₁ = 40 km
The distance the truck then covers with the average speed of 40 km/h, d₂ = 40 km
[tex]Average \ speed = \dfrac{Total \ distance}{Time}[/tex]
[tex]\therefore time, \, t = \dfrac{Total \ distance}{Average \ speed}[/tex]
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(80 km·h) t₁ = 0.5 hour
The time it takes the truck to cover the 40 km at 80 km/h = 40 km/(40 km·h) t₂ = 1 hour
The total time taken to cover both 40 km distances, t = t₁ + t₂
∴ The total time taken to cover both 40 km distances, t = (0.5 + 1) hour = 1.5 hours
The total distance covered at both speeds, d = d₁ + d₂
∴ d = 40 km + 40 km = 80 km
The average speed of the truck for the total distance, [tex]v_{average}[/tex] = d/t
∴ [tex]v_{average}[/tex] = 80 km/1.5 hours = 53.[tex]\overline 3[/tex] km/h ≈ 53 km/h
The average speed of the truck for the total distance, [tex]v_{average}[/tex] ≈ 53 km/h
The correct option is (d) 53 km
4. The heat, 'H', developed by the electric iron is given by the following formula;
H = I²·R·t
Where;
I = The current flowing in the electric iron = 5 A
R = The resistance of the iron = 20Ω
t = The time duration of the flow of the current = 30 s
∴ H = (5 A)² × 20 Ω × 30 s = 15,000 joules
The heat, developed by the electric iron, H = 15,000 joules
5. Let 'R' represent the resistance between A and B in each network
a) For the first network, we have;
1/R = 1/(2 + 2) + 1/(2 + 2) = 1/4 + 1/4 = 1/2
∴ R = 2 Ω
∴ The resistance between A and B is 2 Ω
b) For the second network, we have;
R = 1/(1/2 + 1/2) + 3 = 4
R = 4Ω
∴ The resistance between A and B is 4 Ω
c) For the third network, we have;
R = 2 + 1/(1/4 + 1/4) + 2 = 6
R = 6Ω
∴ The resistance between A and B is 6 Ω
d) For the fourth network, we have;
R = 1/(1/2 + 1/2) + 1/(1/2 + 1/2) = 2
R = 2Ω
∴ The resistance between A and B is 2 Ω
A 15.0 cm object is 12.0 cm from a convex mirror that has a focal length of -6.0 cm. What is the height of the image produced by the mirror?
–5.0 cm
7.5 cm
-7.5 cm
5.0 cm
Answer:
-7.5
Explanation:
edge 2021
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Answer:
Ok.............
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In the diagram below, what is the potential difference across the 3.0-ohm resistor?
Answer:
3V
Explanation:
From the question given above, we can see clearly that the resistors are arranged in parallel connection. Hence, the same voltage will pass through the resistors i.e
Total voltage = voltage of 3 Ω = voltage of 6 Ω
From the question given above,
The total voltage = 3 V
Therefore,
Voltage of 3 Ω = total voltage
Voltage of 3 Ω = 3V
Thus, option 3 gives the correct answer to the question.
Which image best illustrates diffraction?
Answer:
The first option- Sun shining through clouds
Explanation:
John has an object suspended in the air. It has a mass of 50 kilograms and is 50 meters above the ground. Calculate the object's potential energy?
which best illustrates the relationships between a producer and a consumer
______________ controls the flow of electric current.
Answer!!!
Please
Answer:
Explanation:
Its resistor
If you want brainiest, can you help me?
Answer
?????
Explanation:
Objects traveling in! acceleration.* motion experience centripetal
Answer:
They travel
Explanation:
Because they move in a certin way
A 7 kg ball is push with a force of 28 N. What is the acceleration? .
Answer:
a = 4 m/s²
Explanation:
Given: 28 N, 7 kg
To find: Acceleration (a)
Solution: To find (a), divide force by weight
A = F ÷ m
= 28 ÷ 7
= 4 m/s²
Newtons are derived units, equal to 1 kg-m/s². In other words, a single Newton is equal to the force needed to accelerate one kilogram one meter per second squared.
How do you calculate kinetic energy without velocity
The kinetic energy is calculated by work done, The work done is equal to the change in kinetic energy when the object is at rest.
Kinetic energy (KE) is calculated using the formula:
KE = (1/2) × mass × velocity²
However, if you don't have the velocity value, it is not possible to calculate the kinetic energy accurately. Velocity is a crucial component in determining kinetic energy because it quantifies the object's speed and direction of motion.
But there is a special case when the object is at rest the change in velocity is equal to the work done.
Therefore, The kinetic energy is calculated by work done, The work done is equal to the change in kinetic energy when the object is at rest.
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