Answer: A.AB
Explanation:
This Velocity vs Time graph shows the acceleration of a body or object, since acceleration is the variation of velocity in time.
As we can see in the attached image, the graph can be divided in four segments:
OA: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a positive slope, hence we are dealing with a positive uniform acceleration.
AB: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be positive. This means the acceleration is nonuniform and positive.
BC: In this segment the acceleration is changing at a nonuniform rate, since in this part it is not possible to calculate the slope. However if this were uniform, the slope woul be negative. This means the acceleration is nonuniform and negative.
CD: In this segment the acceleration is changing at a uniform rate. In addition we can see it has a negative slope, hence we are dealing with a negative uniform acceleration.
From all these segments, the only one that fulfils the nonuniform positive acceleration condition is option A:
Segment AB
Answer:
AB plato users ;)
Explanation:
How does the scattering of tiny particles in the air affect the colors of the sky at sunrise and sunset
It affects the colors of the sky at sunrise and sunset because only the longer-wavelengths colors are visible.
What are two examples of observations you might make, and two examples of inferences you might make, when looking at logs burning in a campfire?
Answer:
One observation would be the change in odor when observing the logs burning in a campfire and because of that a inference could be because a change in odor is occurring, a chemical change is happening to the logs (combustion).
A second observation would be that the wood being burned gave off smoke at first but then stopped and because of that a inference would be that the compound that were being burned creating the smoke was all evaporated from the wood.
a substance has a melting point of 0°C and a boiling point of 100°F. The substance is most likely..
1.) Water
2.) Hydrogen
3.) Gold
4.) Table Salt
the kind of graph that would best show the
results of a survey of 144 people where 75 ride a bus, 45 drive cars,
15 carpool, and 9 walk to work.
Answer:
a bar graph would be the kind of graph that you should use for this problem because it would be easier to read and also do
Explanation
A Pie Chart is the best type of graph to represent the results of this survey, as it visually expresses each commuting mode as a portion of the total survey responses.
Explanation:The type of graph that would present this data most clearly is a Pie Chart. The Pie Chart would provide a visual representation of each commuting method as a proportion of the total survey responses. For instance, the section corresponding to bus riders would be rather large, as 75 out of 144 individuals, or approximately 52% of the participants, use the bus. In contrast, the segment for individuals who walk would be smaller, as 9 out of 144 or about 6% of respondents walk to work. As such, a Pie Chart offers a visual distribution of responses, making it easy to compare different categories.
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A box is being pulled to the right. What is the direction of the gravitational force?
up
down
Oright
left
Answer:
The correct answer would be downwards
Hope this helps have a good day
Final answer:
The gravitational force on a box being pulled to the right is downward towards the Earth's center.
Explanation:
The direction of the gravitational force on a box being pulled to the right is downward towards the Earth's center. This is because gravitational force is a vector that points downwards, regardless of any horizontal movement or force applied to an object. The gravitational force can be calculated using the equation F = mg, where F is the gravitational force, m is the mass of the object, and g is the acceleration due to gravity, which is approximately 9.81 m/s² near the Earth's surface. Therefore, even when the box moves to the right, the gravitational force only acts downward.
What is needed to create change in a system?
19) Suppose that a car traveling to the east (+x direction) begins to slow down as it approaches a traffic
light. Which statement concerning its acceleration must be correct?
A) Its acceleration is in the -x direction.
B) Its acceleration is zero.
Its acceleration is decreasing in magnitude as the car slows down.
D) Its acceleration is in the +x direction.
Answer: C) Its acceleration is decreasing in magnitude as the car slows down.
Explanation:
According to the described situation the car's final velocity is less than its initial velocity, this means the car's velocity decreased as it slows down.
On the other hand, acceleration [tex]a[/tex] is defined as the variation of velocity in time:
[tex]a=\frac{\Delta V}{\Delta t}[/tex]
If the car's velocity decreases, its acceleration is negative. Hence, the acceleration is decreasing in magnitude as well.
In the context of a car slowing down while traveling east, its acceleration must be in the -x direction (towards the west) which means its acceleration is in the opposite direction of its motion, hence option A is correct.
The question concerns the acceleration of a car traveling east (considered the +x direction) as it begins to slow down when approaching a traffic light. According to the principles of physics, when an object is slowing down, its acceleration is in the opposite direction of its motion. Since the car is moving to the east and slowing down, its acceleration must be towards the west, which is the -x direction in our coordinate system. Therefore, its acceleration is in the -x direction, making the correct answer to the question Option A.
To further clarify, when a car traveling in a positive direction (to the east in this case) decelerates or slows down, it undergoes negative acceleration because the deceleration is opposite to the direction of its velocity. Hence, in the context of our coordinate system where the east is positive, the westward acceleration (slowing down) is considered negative.
With which part of the brain is awareness typically associated?
Answer:cerebral cortex
Explanation:
Answer:
Cerebral Cortex
Explanation:
The cerebral cortex has a left and a right hemisphere. Each hemisphere can be divided into four lobes: the frontal lobe, temporal lobe, occipital lobe, and parietal lobe. The lobes are functional segments. They specialize in various areas of thought and memory, of planning and decision making, and of speech and sense perception.
Melanie watched the path a baseball followed after a pitcher threw it. She noticed that the ball traveled horizontally away from the pitcher as well as downward toward the ground. What force caused the ball to accelerate in the downward direction when it was thrown?
Answer:gravity
Explanation:
Gravity is the force that causes a baseball to accelerate downward when thrown, resulting in a constant negative vertical acceleration that contributes to the ball's parabolic trajectory.
Explanation:The force that causes a baseball to accelerate downward when thrown is gravity. Despite the ball traveling horizontally away from the pitcher, gravity acts downwards upon the ball from the moment it leaves the pitcher's hand until it contacts the ground. This creates a parabolic trajectory, characterized by a vertical acceleration that is constant over time, as indicated by the ball's motion being split into two perpendicular components: horizontal motion due to the initial throw, and vertical motion due to the force of gravity.
The graph of the ball's vertical acceleration versus time would show a negative value that remains constant, representing the unchanging acceleration due to gravity in the downward direction, which is typically approximately -9.8 m/s2 near Earth's surface. This downward acceleration is independent of the ball's horizontal velocity.
possible data where using a bar graph
would be better than using a line graph.
Answer:
Make a graph that represents exotic pet ownership in the United States. There are 8,000,000 fish, 1,500,000 rabbits, 1,300,000 turtles, 1,000,000 poultry and 900,000 hamsters.
Explanation:
The biggest difference is that bar graphs are more versatile while line graphs are better for showing trends over time or another measure with a logical progression of values (such as distance from a given point). Bar graphs can also show frequency distributions (how often you observe different outcomes) much more effectively than line graphs.
Line charts should be used only for time series (chronological) or when there is some other sequence to the dimensions on the x-axis, e.g. dates, months, sequence of stages of a project, sequence of meters along on a gas pipeline, and they should be used to detect trends and patterns, not to give people exact quantitative readings.
Bar charts should be used for comparing specific x-axis values, though they can certainly be used for time series, like line charts. They can also be used to display parts of a whole in favor of pie charts, in which case, the space between the bars should be reduced.
When the volleyball is below your shoulders you need to?
Answer:
You need to Bump the volleyball
hope it helps :)
Which of the following represents the wavelength of a wave?
Diagram of a wave. The point between the highest and lowest points is labeled A; the height is labeled B; the highest point is labeled C; the distance between the highest points of consecutive waves is labeled D.
A
B
C
D
Answer: D. the distance between the highest points of consecutive waves
Explanation:
The wavelength of a wave is defined as the distance traveled by a periodic perturbation that propagates through a medium in a given time interval. It is usually represented by [tex]\lambda[/tex] and can be calculated if the frequency of the wave is known, since there is an inverse relationship between both.
In the specific case of a periodic sine wave (which is the way in which a wave is usually represented graphically) the wavelength can be determined as the distance between two consecutive maxima of the disturbance.
Therefore, the correct option is D.
Answer:
Explanation:
D. the distance between the highest points of consecutive waves
Graph y=2 line find value of y when x =5
Explanation:
y=2 is a straight horizontal line through the point y=2.
As such for all x-values, the y-value will be the same which is y=2 in this case.
LOOK AT THE EQUATION !
The equation tells everything that Y depends on, and what the exact value of Y is for every possible value of all the things that it depends on.
THIS equation says: "The value of Y depends on '2'. At every moment, no matter what the value of '2' is, Y is equal to it."
The equation tells you that.
So now, we can actually tell the future ! We know that the value of '2' is always going to be TWO. If we use the powerful equation that we have, we know that Y is always going to be TWO.
Does the value of Y depend on the value of X ? If it does, then X must be there on the right side of the equation. But X is not there ! That means that X has no influence on the value of Y. Y is always 2 !
You say X=5 ? That's nice. Who cares ? ! ? It has no influence on Y . Y is ALWAYS 2 .
If the change in position Dx is related to velocity v (with units of m/s) in the equation Dx=Av, the constant A has which dimension ?
Answer: seconds
Explanation:
We have the following equation:
[tex]Dx=A.V[/tex]
Where [tex]Dx[/tex] has unit of meters ([tex]m[/tex]) and [tex]V[/tex] has units of meters per second ([tex]m/s[/tex]).
If we input these units in the equation, we will have:
[tex]m=A(m/s)[/tex]
Clearing [tex]A[/tex]:
[tex]A=\frac{m.s}{m}=s[/tex]
Hence [tex]A[/tex] is related to time, and its unit in this case is second.
5. A car is traveling at 100 km/hr. How many hours will it take to cover a displacement of 750 km?
Answer:
It will take 1 hour for a car to cover a displacement of 750 km at a constant speed of 100 km / hr.
Explanation:
Velocity is associated with the change of position of a body over time. In other words, speed expresses the relationship between the space traveled by an object, the time taken for it and its direction.
That is, speed implies the change of position of an object in space within a certain amount of time (that is, speed), added to the direction in which said movement occurs.
Then, 100 km / hr is the speed of the car and indicates that every hour the car travels 100 kilometres.
Then it is possible to apply a rule of three to calculate the time it takes for the car to travel 750 km. The three employee rule is: if 100 km are traveled in 1 hour, 750 km in how long is it traveled?
[tex]time=\frac{750 km*1hour}{100 km}[/tex]
time=7.5 hour
It will take 1 hour for a car to cover a displacement of 750 km at a constant speed of 100 km / hr.
Pls help I rlly don’t understand
Answer: Over time, the objects velocity or speed over time is gradually increasing. For the second one, the line is also showing that the rate at which the objects velocity is increased is constant, since the slope is constant.
At the end of the 4th half-life, how much of a material will have decayed?
93.75% of a material decays at the end of [tex]4^{th}[/tex] half-life.
Explanation:
The time needed by a material to reduce its initial amount into half is called half-life. It is generally used term in nuclear physics. This is to explain how fast unstable atom undergoes, or how long can stable atoms present, and radioactive decay.
Decay % of material after each half-life to be calculated as follows,
After one half-life- 50% original, and 50% product decayed.
After two half-life- 25% original, and 75% product decayed.
After three half-lives- 12.5% of original, and 87.5% of decay product.
After four half-lives- 6.25% original, and 93.75% of decay product.
Answer:
15/16
Explanation:
On a 100m straight track, Zak runs to the 80m mark in 15s. He then runs back to the 20m in 10s. He then runs to the 100m mark in 20s. Finally he runs to the 70m mark in 5s. The total distance travelled by Zak is ____ m and total displacement is ____ m.
Answer:
The total distance traveled by Zak is 250 m and total displacement is
70 m
Explanation:
Distance is a scalar quantity that represents how much ground an
object has covered during its motion
Displacement is a vector quantity that represents how far out of place
an object is, means the change in its position
Displacement = final position - initial position
The straight track is 100 m
Zak runs to the 80 m mark
That means he runs forward from zero to 80
Then his distance = 80 m
His displacement = + 80 m
He then runs back to the 20 m
That means that he runs back from 80 m to 20 m
Then his distance = 80 - 20 = 60 m
His displacement = 20 - 80 = -60 m
He then runs to the 100 m mark
That means he runs forward from 20 m to 100 m
Then his distance = 100 - 20 = 80 m
His displacement = 100 - 20 = + 80 m
Finally he runs to the 70 m mark
That means he runs back from 100 m to 70 m
Then his distance = 100 - 70 = 30 m
His displacement = 70 - 100 = - 30 m
His total distance is the sum of all distances he runs
The total distance = 80 + 60 + 80 + 30 = 250 m
His total displacements is the sum of all displacements he runs
The total displacement = (+80) + (-60) + (+80) + (-30) = + 70 m
The total distance traveled by Zak is 250 m and total displacement is
70 m
A scientific theory
1)Holds the highest level of acceptance
2)Explains a number of facts
3)Uses specific hypotheses and descriptive laws that have been well-tested
4)All of the above
5)None of the above
Answer: 4
Explanation: the scientific theory i believe can do all of the answer that are listed above
Answer: 4)All of the above
Explanation:
A scientific theory is the detailed explanation for the cause of natural process, natural event occurring in the world. It can be tested on the basis of the experimental trials, and direct observations. Thus this holds the validity in results and accepted by the entire scientific community.
It holds the highest level of acceptance from all over the world and especially by the scientific communities. It also explains a number of facts those were unknown. The theory is supported by the descriptive laws and a hypothesis is created in before the actual generation of the theory so as to prove the facts experimentally.
A boy is pulling a load of 150N with a string inclined at an angle 30 to the horizontal if the tension of string is 105N the force tending to lift the load off the ground is
The force tending to lift the load (vertical force) is equal to 22.5N.
Why?
Since the boy is pulling a load (150N) with a string inclined at an angle of 30° to the horizontal, the total force will have two components (horizontal and vertical component), but we need to consider the given information about the tension of the string which is equal to 105N.
We can calculate the vertical force using the following formula:
[tex]VerticalForce=Force*Sin(30\° )=(BoysForce-StringForce)*\frac{1}{2}\\\\VerticalForce=(150N-105N)*\frac{1}{2}=VerticalForce=45N*\frac{1}{2}=22.5N[/tex]
Hence, we can see that the force tending to lift the load off the ground (vertical force) is equal to 22.5N.
Have a nice day!
A human hair is approximately 56 µm in diameter.
Express this diameter in meters.
Answer in units of m
Answer:
The diameter is 0.000056 m
Explanation:
Lets explain the relation between the meter and the micrometer
1 Meter is equal to 1000000 (one million) micrometers
1 micrometer = [tex]\frac{1}{1000000}=\frac{1}{10^{6}}=10^{-6}[/tex]
The symbol of the meter is m
The symbol of micrometer is μm
A human hair is approximately 56 µm in diameter
We need to express this diameter in meter
To do that we divide this number by 1,000,000 or multiply it by [tex]10^{-6}[/tex]
→ [tex]\frac{56}{1000000}=0.000056[/tex] 56 µm = 0.000056 m
→ OR
→ [tex]56*10^{-6}=0.000056[/tex]
→ 56 µm = 0.000056 m
The diameter is 0.000056 m
If a glass is knocked off of a table that is 2.6 m tall, how long does it take for the glass to hit the ground? FILL IN All GUESS STEPS TO GET CREDIT. CHECK EXAMPLE PROBLEM BELOW.
Answer:
0.73 s
Explanation:
The glass is in free fall, so its vertical position at time t is given by the equation:
[tex]y(t) = h + ut + \frac{1}{2}gt^2[/tex]
where
h = 2.6 m is the initial height
u = 0 is the initial velocity of the glass
[tex]g=-9.8 m/s^2[/tex] is the acceleration of gravity (downward since it is negative)
We want to know the time t at which the glass reaches the ground, so when
y(t) = 0
So the equation becomes
[tex]0 = h + \frac{1}{2}gt^2[/tex]
And solving for t, we find
[tex]t=\sqrt{\frac{-2h}{g}}=\sqrt{\frac{-2(2.6)}{-9.8}}=0.73 s[/tex]
Answer:
0.73 sec
Explanation:
formula:X=ViT+(0.5)AT^2
2.6=(0)T+(0.5)(9.8)T^2
cancel:(0)T
2.6=(0.5)(9.8)T^2
take 0.5 to other side and divide with 2.6
5.2=(9.8)T^2
now do the same with 9.8
0.530612 and square root it because u can't leave the T^2
you'll get t=0.73 s
which object has a net force of -68
It is difficult to identify a specific object with a net force of -68 without more detailed context. However, we can understand that net force is the vector sum of all forces acting on an object, and it is calculated using Newton's Second Law of Motion: F = ma.
Explanation:The question is about identifying an object with a net force of -68. A net force is the vector sum of all forces acting upon an object. In physics, negative force usually indicates that the force is acting in the opposite direction of the positive axis of a graph. It is challenging to precisely identify the object with a net force of -68 from the given information; we would need more detailed context such as the direction the force is applied or the object's mass. However, the principle of net force can be described using Newton's Second Law of Motion, which states F = ma where F is the net force, m is the mass, and a is the acceleration.
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The object with a net force of -68 N can be determined by considering the vector sum of the forces acting on it. In this case, the net force is approximately 73.76 N and directed at an angle of about 59.9 degrees below the negative x-axis.
Explanation:The object with a net force of -68 N can be determined by considering the forces acting on it.
A free-body diagram shows a northward force of 64 N and a westward force of 38 N.
The net force is the vector sum of the two forces, which can be found using the Pythagorean theorem.
In this case, the net force is approximately 73.76 N and directed at an angle of about 59.9 degrees below the negative x-axis.
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4.) An apartment building is on fire and a guy is trapped on the fire escape ladder. There is a
dumpster that is 6.3m away and is filled full of trash, and he is 7m above it. If he jumps totally
in the horizontal direction, how fast does he have to jump in order to land in the dumpster?
Answer:
5.3 m/s
Explanation:
First, find the time it takes for him to fall 7m.
y = y₀ + v₀ t + ½ at²
0 = 7 + (0) t + ½ (-9.8) t²
0 = 7 − 4.9 t²
t ≈ 1.20 s
Now find the velocity he needs to travel 6.3m in that time.
x = x₀ + v₀ t + ½ at²
6.3 = 0 + v₀ (1.20) + ½ (0) (1.20)²
v₀ ≈ 5.27 m/s
Rounded to two significant figures, the man must run with a speed of 5.3 m/s.
What are 5 most important facts should be known the movement of heat energy?
Explanation:
heat energy is the movement of molecules or atoms in solids, liquids and gases.
facts about movement of heat energy.
1) heat energy transferred through three main processes that are: conduction , convention and radiations.
2) our earth absorbs energy coming from sun through radiation.
3) entire universe is made up of atoms when they moves they transfer heat.
4) heat energy can change the state of matter as it causes melting.when a solid such as ice absorb heat energy it convert into liquid.
5) heat energy keeps moving until both objects reach at same temperature.
The movement of heat energy involves thermal conductivity, heat transfer methods, specific heat, conservation of energy, and spontaneous heat transfer. These fundamental principles explain how heat energy moves and transforms within systems. Understanding these concepts is crucial in practical applications such as cooking and climate control.
The movement of heat energy, also known as heat transfer, is a fundamental topic in physics. Here are the five most important facts to know:
Thermal Conductivity: Matter has a property called thermal conductivity that determines how well it can transfer heat. For example, metals generally have high thermal conductivity, making them good conductors of heat.Heat Transfer Methods: Heat energy can be transferred through conduction, convection, and radiation. Conduction occurs in solids where molecules transfer energy by vibrating in place, convection occurs in fluids (liquids and gases) through the movement of the fluid itself, and radiation involves the transfer of heat through electromagnetic waves.Specific Heat: The specific heat of a substance indicates how much energy is required to raise the temperature of one gram of the substance by one degree Celsius. For instance, water has a high specific heat, meaning it requires more energy to heat up or cool down compared to many other substances.Conservation of Energy: According to the law of conservation of energy, energy cannot be created or destroyed, only transferred or converted from one form to another. This principle is crucial in understanding how heat energy moves and transforms within systems.Spontaneous Heat Transfer: Energy is transferred spontaneously from a higher temperature system to a lower temperature system. This is the fundamental process of heat transfer known as heat flow.These concepts are essential for understanding various physical phenomena and applications, such as cooking, climate control, and engineering systems.
Which of the following will not conduct an electrical current?
pure water
tap water
aquarium water
ocean water
Answer:
Pure water won’t conduct electricity
Option A
Explanation:
Pure water doesn’t contain salts or impurities. It is the salts that dissociate to form ions that act as charge carriers in conducting solutions. For a medium to conduct electricity it should have carriers to carry the electrical charge.
Thus absence of charge carriers make pure water non conducting. Charge carriers in metals are electrons and in ionic solutions they are positive and negative ions.
Tap water, aquarium water and ocean water contains dissolved electrolytes. When electricity is passed through them the electrolytes dissociates into ions and these ions conduct electricity.
Answer:
pure water. plz vote brainliest
Explanation:
A 50 newton force is required to push a 10 kg box 30 meters across the floor. The box is then lifted up 6 meters and placed on a shelf. How much total work was done?
Answer:
2088 J
Explanation:
Work = net force × distance
When the box is being pushed across the floor, the force is 50 N, and the distance is 30 m.
W = (50 N) (30 m)
W = 1500 J
When the box is being lifted, the force is the weight of the box (10 kg × 9.8 m/s²), and the distance is 6 m.
W = (98 N) (6 m)
W = 588 J
So the total work done is:
W = 1500 J + 588 J
W = 2088 J
A nonuniform, but spherically symmetric, distribution of charge has a charge density ρ(r) given as follows:
ρ(r)=ρ0(1−r/R) for r≤R
ρ(r)=0 for r≥R
where ρ0=3Q/πR3 is a positive constant.
Express your answer in terms of some or all of the variables r, R, Q, and appropriate constants.
Obtain an expression for the electric field in the region r≥R.
Obtain an expression for the electric field in the region r≤R.
Find the value of r at which the electric field is maximum.
Find the value of that maximum field.
Answer:
r ≥ R, E = Q / (4πR²ε₀)
r ≤ R, E = 12Q (⅓ (r/R)³ − ¼ (r/R)⁴) / (4πr²ε₀)
Maximum at r = ⅔ R
Maximum field of E = Q / (3πε₀R²)
Explanation:
Gauss's law states:
∮E·dA = Q/ε₀
What that means is, if you have electric field vectors E passing through areas dA, the sum of those E vector components perpendicular to the dA areas is equal to the total charge Q divided by the permittivity of space, ε₀.
a) r ≥ R
Here, we're looking at the charge contained by the entire sphere. The surface area of the sphere is 4πR², and the charge it contains is Q. Therefore:
E(4πR²) = Q/ε₀
E = Q / (4πR²ε₀)
b) r ≤ R
This time, we're looking at the charge contained by part of the sphere.
Imagine the sphere is actually an infinite number of shells, like Russian nesting dolls. For any shell of radius r, the charge it contains is:
dq = ρ dV
dq = ρ (4πr²) dr
The total charge contained by the shells from 0 to r is:
q = ∫ dq
q = ∫₀ʳ ρ (4πr²) dr
q = ∫₀ʳ ρ₀ (1 − r/R) (4πr²) dr
q = 4πρ₀ ∫₀ʳ (1 − r/R) (r²) dr
q = 4πρ₀ ∫₀ʳ (r² − r³/R) dr
q = 4πρ₀ (⅓ r³ − ¼ r⁴/R) |₀ʳ
q = 4πρ₀ (⅓ r³ − ¼ r⁴/R)
Since ρ₀ = 3Q/(πR³):
q = 4π (3Q/(πR³)) (⅓ r³ − ¼ r⁴/R)
q = 12Q (⅓ (r/R)³ − ¼ (r/R)⁴)
Therefore:
E(4πr²) = 12Q (⅓ (r/R)³ − ¼ (r/R)⁴) / ε₀
E = 12Q (⅓ (r/R)³ − ¼ (r/R)⁴) / (4πr²ε₀)
When E is a maximum, dE/dr is 0.
First, simplify E:
E = 12Q (⅓ (r/R)³ − ¼ (r/R)⁴) / (4πr²ε₀)
E = Q (4 (r³/R³) − 3 (r⁴/R⁴)) / (4πr²ε₀)
E = Q (4 (r/R³) − 3 (r²/R⁴)) / (4πε₀)
Take derivative and set to 0:
dE/dr = Q (4/R³ − 6r/R⁴) / (4πε₀)
0 = Q (4/R³ − 6r/R⁴) / (4πε₀)
0 = 4/R³ − 6r/R⁴
0 = 4R − 6r
r = ⅔R
Evaluating E at r = ⅔R:
E = Q (4 (⅔R / R³) − 3 (⁴/₉R² / R⁴)) / (4πε₀)
E = Q (8 / (3R²) − 4 / (3R²)) / (4πε₀)
E = Q (4 / (3R²)) / (4πε₀)
E = Q (1 / (3R²)) / (πε₀)
E = Q / (3πε₀R²)
For question 1:
For the region [tex]r \geq R[/tex], an expression for the electric field can be calculated by using the Gauss law:
Use gauss law of electrostatics, the charge electric flux through the Gaussian surface is,
[tex]\int \vec{E} \cdot d\vec{A}=\frac{q_{enc}}{\varepsilon_{0} }\\\\E(4\pi r^2)=\frac{Q}{\varepsilon_0}\ \ \ \ \ \ \ \ \ \ \ \ \ (Since\ \ q_{enc}=Q )[/tex]
Here, Q is the enclosed charge and [tex]\varepsilon_0[/tex] , is the permeability.
[tex]E=\frac{1}{4\pi \varepsilon_0 } \frac{Q}{r^2}[/tex]
Therefore, the required electric field is [tex]\frac{Q}{4\pi\varepsilon_0 r^2 }[/tex]
For question 2:
For Gaussian sphere of radius [tex]r \leq R[/tex], the charge enclosed within a spherical shell is,
[tex]dq =\rho_0(1-\frac{r}{R}) 4\pi r^2 dr[/tex]
Hence, the total charge enclosed with in the radius r is as follows,
[tex]q_{enc}=\int^{r}_{0} \rho_{0} (1-\frac{r}{R}) 4\pi r^2 \ dr\\\\[/tex]
[tex]=4\pi \rho_0 |\frac{r^3}{3}-\frac{r^4}{4R}|^4_{0}\\\\=\frac{12 Q}{R^3}(\frac{r^3}{3}-\frac{r^3}{4R})\\\\=\frac{Qr^3}{R^3}(4-\frac{3r}{R})\\\\[/tex]
Use Gauss's law for the Gaussian sphere of radius r,
[tex]\int \vec{E}\cdot dA=\frac{q_{enc}}{\varepsilon_0}\\\\E(4\pi r^2)=\frac{Qr^3}{\varepsilon_0 R^3}(4-\frac{3r}{R})\\\\E=\frac{Qr}{4\pi \varepsilon_0 R^3}(4-\frac{3r}{R})\\\\[/tex]
Therefore, the required electric field at [tex]r\leq R[/tex] is [tex]\frac{Qr}{4\pi \varepsilon_0 R^3}(4-\frac{3r}{R})\\\\[/tex]
For question 3:
The change in electric filed with respect to distance is zero when the electric field has a maximum value.
[tex]\frac{dE}{dr}= 0\\\\\frac{d(\frac{Qr}{4\pi \varepsilon_0 R^3}(4-\frac{3r}{R}))}{dr}=0\\\\(\frac{Q}{4\pi \varepsilon_0 R^3})\frac{d(4r-\frac{3r^2}{R})}{dr}=0\\\\[/tex]
Here, [tex](\frac{Q}{4\pi \varepsilon_0 R^3})[/tex] is not equal to zero. Hence,
[tex]\frac{d(4r-\frac{3r^2}{R})}{dr}=0\\\\4-\frac{6r}{R}=0\\\\r=\frac{4R}{6}=\frac{2R}{3}[/tex]
Therefore, the required value of [tex]r \ \ is\ \ \frac{2R}{3}\\\\[/tex]
For question 4:
Maximum value of the electric filed is as follows
[tex]E= \frac{Q}{4\pi \varepsilon_0 R^3} (4-\frac{3r}{R})\\\\[/tex]
[tex]= \frac{Q(\frac{2R}{3})}{4\pi \varepsilon_0 R^3} (4- \frac{3(\frac{2R}{3})}{R})\\\\=\frac{Q}{3 \pi \varepsilon_0 R^2}[/tex]
Therefore, the required maximum value of the electric field is [tex]\frac{Q}{3 \pi \varepsilon_0 R^2}[/tex]
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brainly.com/question/12577441
A force of 15 newtons is applied to both Object A with a mass of 25 kilograms and Object B with a mass of 50 kilograms. What is true about the
acceleration of Object A and Object B?
Answer:
Acceleration of Object A = 0.6 m/s²
Acceleration of Object B = 0.3 m/s²
Acceleration of Object A is double than the acceleration of Object B.
Explanation:
According to the Newton's 2nd law of motion, Acceleration of an object by a net force is directly proportional to the magnitude of that net force and in the direction of that net force and inversely proportional to the mass of the object
Mathematically
F ∝ a
F = ma
Given data:
F = 15 N
m₁ = 25 kg
m₂ = 50 kg
F = m₁a₁
a₁ = F/m₁
a₁ = 15/25
a₁ = 0.6 m/s²
F = m₂a₂
a₂ = F/m₂
a₂ = 15/50
a₂ = 0.3 m/s²
It can be seen that acceleration of Object A is double than the acceleration of Object B.
A block with mass m = 6 kg is sitting on a horizontal surface and not moving. The free-fall acceleration is g = 9.81 m/s2. Please answer the following questions.
a. Write an expression for the magnitude of the force of gravity Fg on the block.
b. Calculate the magnitude of the force of gravity Fg on the block in Newtons.
c. In what direction is the force of gravity in this problem?
d. What is the magnitude of the normal force FN in Newtons?
e. In what direction does the normal force act?
Answer:
a. expression for force of gravity is mg
b. Value of force of gravity is 58.86 N
c. Direction of force of gravity is downwards
d. Value of normal force is -58.86 N
e. direction of normal force is upwards.
Explanation:
Given that mass of the block [tex]m=6 kg[/tex]
acceleration due to gravity [tex]g=9.81 m/s^2[/tex]
a. Expression for force of gravity is [tex]F_g=m\times g[/tex]
b. [tex]F_g=mg=6 \times 9.81=58.86 N[/tex]
force of gravity is [tex]58.86 N[/tex]
c. Force of gravity always acts in the downward direction.
d. Normal force[tex]F_N[/tex] acts in the direction opposite to the weight of the block and their magnitudes are same. since the object is at rest the upward and downward forces on the block are balanced.
[tex]F_N=-F_g=-58.86 N[/tex]
e. Normal force [tex]F_N[/tex]acts in the upwards.
The force of gravity on a 6 kg block is 58.86 N, acting downwards, while the normal force is 58.86 N, acting upwards, since the block is stationary on a horizontal surface.
Explanation:Forces Acting on a Stationary Block
a. The expression for the magnitude of the force of gravity Fg on the block is given by Newton's second law of motion: Fg = m × g where m is the mass of the object and g is the acceleration due to gravity.
b. To calculate Fg, simply multiply the mass m by the acceleration due to gravity g: Fg = 6 kg × 9.81 m/s² which equals 58.86 N.
c. In this problem, the direction of the force of gravity is vertically downwards, towards the center of the Earth.
d. The magnitude of the normal force FN on the block is equal to the force of gravity acting on the block when it is stationary on a horizontal surface, therefore FN = 58.86 N.
e. The normal force acts in a direction perpendicular to the surface, which in this case is vertically upwards.