If a 0.6 kg squirrel falling at 14 m/s hits a pile of leaves and comes to rest in 2 s , the normal force of the leaves on the squirrel as it comes to rest would be 4.2 Newtons.
What is Newton's second law?Newton's Second Law states that The resultant force acting on an object is proportional to the rate of change of momentum.
As given in the problem a 0.6 kg squirrel falling at 14 m/s hits in a pile of leaves and comes to rest in 2 s.
The change in the moment of the squirrel = 0.6 × 14
=8.4 Kg - m/s
The normal force = rate of the change of the momentum
= 8.4 / 2
= 4.2 Newtons
Thus, the normal force of the leaves on the squirrel as it comes to rest would be 4.2 Newtons.
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32. Use billiard balls to model the motion of particles in a gas. Use students in a crowded
hallway to model the motion of particles in a liquid. Use an audience in a movie theater to model the
motion of particles in a solid.
55
The particles of a solid are in fixed positions, the particles of a liquid do not translate to a large extent while the particles of a gas has extreme degree of freedom.
What are particles?We have to refer to the kinetic molecular theory at this point. We would recall from the theory that the particles that compose a substance are said to be in a constant random motion. As such, the molecules of a gas do have the greatest degree of freedom thus they move about freely. On the other hand, the molecules that compose a solid have the least degree of freedom as they remain in their fixed positions and can only vibrate.
Billiard balls are free to have about and they move at high speeds since they are spaced from each other. This is the nature of the interaction between the molecules of a gas.
Students in a hall way that is crowded can be used to approximate liquid particles because they do not posses a high degree of freedom but the molecules could move a few inches away from each other.
For a solid. an apt approximation is the audience in a movie theater. This is because, they can only remain on their seats just as the particles in a solid retain a fixed position and do not translate.
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Two students carried out an experiment to determine the speed of sound. This is the method used
Student A stands 100 m away from Student B.
1
2
3
4.
5.
Student A bangs two blocks of wood together making a loud sound.
Student B starts a stopclock when he sees the blocks of wood bang together.
Student B stops the stopclock when he hears the sound and records the time.
The students repeat steps 2-4 several times.
The students calculated the speed of sound from their results.
(e) Suggest the most likely source of error in the experiment.
The most likely source of error would be human error such as delay in stopping the stopwatch. The coordination error would be the source of error.
What is the speed of Sound?On Earth, the speed of sound as calculated experimentally at sea level assuming a default air temperature of 59 degrees Fahrenheit (15 degrees Celsius) is 761.2 mph (1,225 km/h). The speed of sound is slowed down because gas molecules move more slowly at lower temperatures.
Thus, sound tends to move faster in warmer air.
To explain what speed of sound is, the speed of sound can be described as the distance travelled per unit of time by any sound wave as it propagates through a completely elastic medium.
At 20 °C, temperature the speed of sound in air is about 343 meters per second, or one kilometer in 2.91 s or one mile in 4.69 s.
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A rock climber stands on top of a 53 m -high cliff overhanging a pool of water. He throws two stones vertically downward 1.0 s apart and observes that they cause a single splash. The initial speed of the first stone was 1.5 m/s. How long after the release of the first stone does the second stone hit the water?
Express your answer to two significant figures and include the appropriate units.
A rock climber stands on the top of a 53 m high cliff overhanging a pool of water, so for 3.1 seconds, after which the second stone hit the water.
What is the average speed?The overall distance the object covers in a given amount of time is its average speed. The scalar quantity represents the average speed. It does not have direction; it is represented by magnitude.
Average Speed= [tex]Total\ Distance/ Total\ time[/tex]
According to the question, the given values are :
v₁ = 1.5 m/s
y₂ = 52 m
y₁ = 0 m
Acceleration, a = 9.8 m/s²
Use Formula :
y₂ = y₁ + v₁t + 0.5 at²
52 = 0 + 1.5t + 0.5 (9.8)t²
4.9 t² + 1.5 t - 52 = 0
[tex]t=-b\frac{+}\ \sqrt{b^2-4ac}/2a[/tex]
t = -1.5 + [tex]\sqrt{2.25+1019.2}[/tex]/9.8
t = (-1.5 + 31.9)/9.8
t = 3.10 seconds.
Hence, the time period will be 3.10 seconds.
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A ball is seen at an initial position of 12m. It moves with an average velocity of 10m/s. How long will it take for the ball to reach the 98m mark?
The ball will take 8.6 sec to reach the 98m mark.
Given,
The initial position of the ball = 12m
The final position of the ball = 98m
The velocity of the ball = 10m/s
The displacement of the ball = (98-12)
= 86m
We know,
Average velocity = Displacement/time
Therefore,
Time = Displacement/velocity
= 86/10
= 8.6 sec
So, the ball will take 8.6 sec with average velocity of 10m/s to reach the mark of 98m from initial position of 12m.
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A tennis player hits a ball vertically with a speed of 10 m/s. How high does it go?
Answer:
5.1 m
Explanation:
Assuming gravitational force is 9.8 m/s², the acceleration experience by the ball is -9.8 m/s²
The acceleration is negative because the ball is moving vertically upward and gravitational force acts vertically downward.
The velocity of the ball at maximum height is 0 m/s when it will start falling back to ground at a positive acceleration of 9.8 m/s²
We can use the following formula to calculate the height the ball reaches
v² = u² + 2 a d
where u is the initial velocity, v = final velocity, a = acceleration and d = displacement(in this case the vertical height from ground)
Final velocity is 0 since the ball has reached it maximum height and starts falling downward, Initial velocity u = 10 m/s
Plugging in values we get
0² = 10² - 2 x 9.8 x d
0 = 100 - 19.6d
Subtracting 100 from both sides
-100 = -4.9 d
Divide by -1 both sides
100 = 4.9d
d = 100/4.9 ≈ 5.1 m
So the ball will reach a height of 5.1m
What layer of the mantle moves with the convection current?
Magma is the layer of the mantle that moves with the convection current.
How does the mantle layer move with convection current?Magma is the molten rock that is present in the mantle below the earth's crust. The high amount of heat and pressure inside the earth leads to hot magma that flows in convection currents. These currents cause the movement of the tectonic plates that formed the earth's crust. Mantle convection is defined as the movement of the mantle that transfers heat from one layer to another. The mantle is heated from the lower side but it is cooled from the upper side so the temperature decreases over long periods.
So we can conclude that the layer of the mantle that moves with the convection current is the magma layer.
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A battery-powered lawn mower has a mass of 49.0 kg. If the net external force
on the lawnmower, including both your push and any resistance, is 28.0 N (about
6.3 pounds), then what will be the magnitude of the mower’s acceleration?
Which one of the following vector pairs is equal in magnitude and opposite in direction?Vectors
explained image
a)one short and one long arrow going towards each other
b)one short and one long arrow going right in the same direction
c)two of the same size arrows going right in the same direction
d)two of the same size arrows going in towards eachother
Select one:
a. A
b. B
c. C
d. D
Answer
(D) the vectors must be the same size and pointing opposite to each other
Which of the answers below are examples of moderate activities?
A- walking slowly, floating in a pool, bicycling 2-3 mph
B- playing video games, sleeping, watching TV
C- bicycling 5-9 mph, walking briskly, recreational swimming
Exercises that register between 3 and 6 METs are considered moderate- intensity activities because they get you moving quickly enough or vigorously enough to burn off three to six times as much energy per minute as you do while you're sitting still.
What purpose do moderate activities serve?Chronic Heart Disease
Your chance of developing these diseases can be decreased by engaging in at least 150 minutes of moderate physical activity each week. By engaging in additional exercise, you can further lower your risk. Additionally, regular exercise helps lower blood pressure and lower cholesterol.
Which courses are moderately paced?Your heart rate will rise while you engage in moderate aerobic activity, and you'll also feel warmer and breathe more quickly than usual.
This may entail taking a quick stroll.
leisurely cycling or cycling on flat land.mild swimmingAquatic exercise.tennis doubles. volleyball.What would you say is moderate intensity exercise?A quick method to gauge relative intensity is the conversation test. In general, you can converse but not sing while engaging in moderate-intensity exercise. In general, you won't be able to speak for more than a few words without pausing to take a breath if you're engaging in vigorous-intensity activities.
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What factors influence the amount of kinetic energy an object has?
By the relation of KE = ½mv²,
the kinetic energy in a body is directly proportional to its mass and square of velocity.
hello please help me out its due today!!
I need to make a word problem using the Ohm's Law, and solve it with shown work, Thank you!
Answer:
no se entiende nada lo siento
Calculate the average velocity of the cart for each fan speed. round your answers to the nearest tenth. the cart with low fan speed has an average velocity of cm/s. the cart with medium fan speed has an average velocity of cm/s. the cart with high fan speed has an average velocity of cm/s.
The average velocity of the cart for each fan speed to the nearest tenth is as follows:
The cart with low fan speed has an average velocity of 67.6 cm/s. The cart with medium fan speed has an average velocity of 78.1 cm/s. The cart with high fan speed has an average velocity of 90.9 cm/s.What is average velocity?An average velocity can be defined as the total distance covered by a physical object divided by the total time taken.
Mathematically, the average velocity of a physical object can be calculated by using this formula:
Average velocity = Total distance/Total time
The average velocity of the cart with low fan speed is given by:
Average velocity = 500/7.4
Average velocity = 67.57 ≈ 67.6 cm/s.
Also, the average velocity of the cart with medium fan speed is given by:
Average velocity = 500/6.4
Average velocity = 78.13 ≈ 78.1 cm/s.
Lastly, the average velocity of the cart with high fan speed is given by:
Average velocity = 500/5.5
Average velocity = 90.91 ≈ 90.9 cm/s.
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a balloon is filled with helium gas how would the balloon volume change if it floated to a higher altitude (p decreases, assume n and t are constant)?
As we know, Pv= nRT where,
P : pressure
V : volume
n : number of moles
R : constant
T : temperature
According to question PV is constant therefore if balloon floats to a higher altitude where the outside pressure is lower than Volume will increase as a result of Boyle's Law. Therefore Figure C represents the final volume.
What is altitude?
A measurement of altitude or height is the distance between a location or item and a reference datum, often in the vertical or "up" direction. Depending on the circumstance, many definitions and reference points are appropriate.
Therefore,
a balloon is filled with helium gas how would the balloon volume change if it floated to a higher altitude (p decreases, assume n and t are constant)?
As we know, Pv= nRT where,
P : pressure
V : volume
n : number of moles
R : constant
T : temperature
According to question PV is constant therefore if balloon floats to a higher altitude where the outside pressure is lower than Volume will increase as a result of Boyle's Law. Therefore Figure C represents the final volume.
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Metals corrode when left exposed to substances in the environment. State why aluminium quickly becomes protected from further corrosion.
Answer:
Explanation: because it develops a thin oxide layer on the surface when the metal comes in contact with oxygen. The oxide layer protect the aluminum against corrosion and if damaged it will immediately regenerate in presence of
Explain the difference between the Bohr model and the electron cloud model.
The main difference between the Bohr model and the electron cloud model is explained as, in Bohr's model, orbital paths around the nucleus are treated as discrete electron energy levels but the electron cloud model is a group of electrons circulating around a nucleus or a molecule. Usually refers to the valence electrons.
Some physical quantities can only have discrete values according to quantum theory, Niels Bohr proposed a hypothesis for the hydrogen atom in 1913 i.e. Only in their predefined orbits do electrons move around a nucleus, if they deviate, the energy difference is released as radiation.Erwin Schrodinger, an Austrian physicist, created the electron cloud model in 1926. It was made up of an electron cloud with many different orbital levels surrounding a dense nucleus i.e. negative electrons circle the positive nucleus at fixed distances from the nucleus.According to Erwin Schrodinger, electrons move in waves, making it impossible to accurately determine where they are at any given time. To determine the probability of an electron existing in a specific place, he created an equation.To know more about Bohr model
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7. Falling objects drop with an acceleration of 9.8 m/s².
If an Olympic high diver steps off the 10 m platform and falls for 1.4s,
what velocity will she enter the water at?
Explanation:
velocity=distance/time
v=10m/1.4sec
Answer:
13 . 7 m/s
Explanation:
v = a t
= acceleration time
= 9.8 m/s^2 * 1.4 s = 13.7 m/s
PLEASE HELP PHYSICS
A miniature quadcopter is located at
xi = −2.25 m
and
yi = −4.70 m
at
t = 0
and moves with an average velocity having components
vav, x = 1.70 m/s
and
vav, y = −1.50 m/s.
What are the x-coordinate and y-coordinate (in m) of the quadcopter's position at
t = 2.60 s?
Answer:
Final coordinates in meters : (2.17, -8.6)
Explanation:
We have the equation
displacement Δd = average velocity x time
In this case there are two components of displacement corresponding to the two components of average velocity
[tex]v_{avg}(x) = 1.70 \; m/s[/tex]
[tex]v_{avg}(y) = -1.50 \; m/s[/tex]
Time traveled is t = 2.60s
So the x component is toward east (+x) axis and y component is due south(-y axis)
[tex]\sf{x \;displacement \;} \Delta_x = v_{avg}(x) x t= 1.70m/s \; \times \; 2.60 = 4.42 m\\\\[/tex]
Since the original x-coordinate was at -2.25m, the end x coordinate is
x = -2.25 + 4.2 = 2.17
The y-displacement
[tex]\sf{y \;displacement \;} \Delta_y = v_{avg}(y) x t\\\\ = - 1.50m/s \; \times \; 2.60 = - 3.9 m\\\\\\\\[/tex]
The starting y-coordinate was at y = -4.70m
So final y-coordinate = -4.7 - 3.9 = -8.6m
Final coordinates in meters : (2.17, -8.6)
A 1167 kg car is driving along a highway with 458,350 J of kinetic energy.
What is its speed?
The speed of the car having kinetic energy 458,350 J is 28.03m/s
What is What is Kinetic Energy ?
Kinetic energy is a type of power that a moving object or particle possesses. An item accumulates kinetic energy when work, which involves the transfer of energy, is done on it by exerting a net force. A moving object or particle has kinetic energy, which depends on both its mass and its rate of motion. The type of motion can be vibration, rotation on an axis, translation (or travel along a path from one place to another), or any combination of these.
K.E = 1/2*m*v2
K.E = kinetic energy
m = mass
v = velocity/speed
458350 = 1/2*1167*v2
v2= 458350*2/1167
v = 28.03 m/s
The speed of the car having kinetic energy 458,350 J is 28.03m/s
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a boy wishes to cross a river in the shortest possible time, without necessarily landing directly across from his starting point. he can row at 2 m/s in still water and the river is flowing at 1 m/s. at what angle θ should he point the bow (front) of his boat?
He should bow his boat at 90° to cross the river.
While the water will push him in side ways, it will not affect the time it takes to actually cross the river.
Hence, the correct answer is 90°.
Factors that have an effect on the velocity of a river consist of the slope gradient, the roughness of the channel, and tides. Rivers generally tend to drift from a higher elevation to a lower elevation. The gradient is the drop of the elevation of a river.
Reverberation is the time taken for the sound to fall beneath the minimal audibility measured from the immediate whilst the supply stopped sounding. Therefore if the reverberation time will become too massive it produces an echo.
Due to velocity of water drift in river, a person either swimming or floating stationary within the river reports a pushing force alongside the flow direction.
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A 10kg block of wood is pulled across a level ground by fore of 15N applied at an angle of 30 degree from the horizontal. How much work is done, if it is moved to a distance of 3m?
The amount of work done, given that the block moved to a distance of 3 m is 38.97 J
How to determine the work doneWork is defined as the product of force and distance moved in the direction of the force.
Work done (Wd) = force (F) × distance (d)
Wd = fd
Considering angle projection,
Wd = FdCosθ
With the above formula, we can detertmine the work done as follow:
Mass (m) = 10 KgForce (F) = 15 NAngle (θ) = 30°Distance (d) = 3 mWorkdone (Wd) =?Wd = FdCosθ
Wd = 15 × 3 × Cos 30
Wd = 45 × Cos 30
Wd = 38.97 J
Therefore, we can conclude that the work done is 38.97 J
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A student releases a marble from the top of a ramp. The marble increases speed while
on the ramp then continues across the floor. The marble travels a total of 220cm in
5.00s.
What was the marble's final speed?
Marble's final speed, Vf = 0.88 m/s
What is displacement and velocity?Vector difference between the final and initial positions of an object is displacement. It is different from the distance the object has travelled along the way.
Velocity is a vector quantity and is defined as the displacement that an object undergoes with respect to time . Meter per second is the standard unit of velocity.
Given distance= 220cm and
time = 5 sec
We can calculate acceleration of the marble by using 2nd equation of motion:
s = Vi t + (1/2)at²
s = distance covered = 220 cm = 2.2 m
Let Vi = initial Velocity
= 0 m/s (as the marble was initially at rest)
To find acceleration, a = ?
2.2 m = (0 m/s)(5 s) + (1/2)(a)(5 s)²
a = (2.2 m)(2) / (5 s)²
a = 0.176 m/s²
Using 1st equation of motion for final velocity (Vf)
Vf = Vi + at
Vf = 0 m/s + (0.176 m/s²)(5 s)
Vf = 0.88 m/s
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what is the initial mechanical energy of the woman falling from the building what is her final mechanical energy
Please help, asap!
Will mark as brainliest!
Answer:
a1)gravity
not sure on others
Explanation:
cause the gravity force pulls u down
Answer:
a) i) Gravitational force
ii) Air resistance
b) (I cannot understand what is the question saying but the unit of acceleration is m/[tex]s^{2}[/tex] or [tex]ms^{-2}[/tex])
ii) Because when the parachutist is falling, the gravitational force is pulling him down. But the air resistance is pushing him upwards acting against the gravitational force resulting in a decreasing acceleration.
iii) This is because soon the air resistance catches up with that of the gravitational force and it cancels the gravitational force so he is falling in a constant velocity. This is called terminal velocity when the gravitational force gets cancelled resulting in a free fall where his weight brings him down.
a 40kg crate rests on a horizontal floor, and a 60kg person is standing on the crate. determine the magnitude of the normal force that the floor exerts on the crate.
The magnitude of the normal force that the floor exerts on the crate is 980 N.
What is normal force?The normal force of an object the perpendicular force of the object due to its weight. The weight of the force of the object due force of gravity.
According to Newton's third law of motion, the normal force of an object is equal and opposite to the weight of the object.
Mathematically, the formula for normal force is given as;
W = Fn
mg = Fn
where;
m is the mass of the objectg is acceleration due to gravityFn is the magnitude of the normal forceSubstitute the given parameters and solve for normal force that the floor exerts on the crate.
Fn = (m1 + m2)g
where;
m1 is mass of the crate m2 is mass of the personFn = (40 + 60)9.8
Fn = (100)9.8
Fn = 980 N
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Not all organelles are found in all cells. For example, red blood cells do not have a nucleus. Imagine looking
at a cell that is responsible for producing a lot of large molecules to be excreted from the cell into the body
(like the cells of the endocrine glands of the pancreas). Predict if you expect to see each of the above
organelles in this cell and then justify your prediction with evidence from this page.
Organelles are small structures present inside the cell body in order to regulate the various functions of cell .
What is an organelle and how does it functions?An organelle is a specialized structure present inside the cell body and is responsible for carrying out various functions.There are numerous cell organelles like cytoplasm, nucleus , nucleolus, mitochondria , golgi apparatus etc.All the cell organelles have specific function inside the cell , depending on whether the cell body is prokaryote or eukaryote.Eukaryotic cell have all the organelles present almost , but prokaryotic cell lacks in few organelles.Its truly said that not all organelles are found in all cells. And red blood cells do not have nucleus.To know more about organelles visit:
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What is Momentum ?
Ty :))
Answer:
Momentum can be well defined as the measure of the kinetic energy of the object. In simple words, the momentum is the product of mass and velocity.
An iodine atom has 53 protons. How many electrons does an
iodine anion have?
Answer:
Since the iodine is added as 1-anion, the number of electrons is 54( 53-(1-) =54
is your interest equal to zero, meaning the line passes through the origin? if not then did we miss something when we said f in equation 5 was only due to spring force
When the angle between the force and the displacement is more than 90 degrees, work might be negative. It can also be zero; if = 90, this will occur.
The spring force, which defines the force applied to an object by the end of an ideal spring, is the most well-known illustration of a force whose value varies on position. An ideal spring will exert a force on the object attached to one end that is proportionate to how much it is stretched, and a force that is proportional to how much it is compressed on the object linked to the other end.
The force must function in order to accomplish its mission have a component that is parallel to the motion's direction or the opposite.
We must compute an integral (a sum) to determine the work done if the force acting on the object is not constant while it is moving.
Assume that an external force with the x component Fx(x) is acting on the object, causing it to travel in a straight line (let's say along the x axis, from xi to xf). (Or, we understand the force Fx to be a function of x.)
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1. What is the direction of the induced current in the front side of the coil?
a. Left
b. Right
c. Up
d. down
2. in what direction is the magnet moving?
a. Away
b. Toward
c. Up
d. Down
1. What is the direction of the induced current in the front side of the coil?
a. Left
b. Right
c. Up
d. down2. in what direction is the magnet moving?
a. Awayb. Toward
c. Up
d. Down
Hope it helps
To determine the direction of the induced current in the front side of the coil and the direction of the magnet's movement, we can use Faraday's law of electromagnetic induction, which states that an induced current is produced in a conductor when it is exposed to a changing magnetic field.
1.) Direction of the induced current in the front side of the coil:
The direction of the induced current can be determined using Lenz's law, which states that the induced current will flow in a direction that opposes the change that caused it.
If the magnet is moving away from the front side of the coil:
The magnetic field through the coil is decreasing. According to Lenz's law, the induced current will flow in a direction to create a magnetic field that opposes this decrease. Applying the right-hand rule for the direction of the magnetic field around a wire, we can determine that the induced current in the front side of the coil will flow counterclockwise when viewed from the front. Therefore, the answer is option a. Left.
2.) If the magnet is moving toward the front side of the coil:
The magnetic field through the coil is increasing. According to Lenz's law, the induced current will flow in a direction to create a magnetic field that opposes this increase. Applying the right-hand rule for the direction of the magnetic field around a wire, we can determine that the induced current in the front side of the coil will flow clockwise when viewed from the front. Therefore, the answer is option b. Right.
Direction of the magnet's movement:
Based on the given information, the options provided (Away, Toward, Up, Down) are not sufficient to determine the exact direction of the magnet's movement. More specific information is needed to determine the direction of the magnet's movement.
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Place a +3q point charge at the origin, and a -q point charge on the x-axis at D = 0.500 m. At what point on the x-axis will the net forces from the other two charges acting on a third charge, q°, be equal to zero?
The Point on the x-axis that the net forces from the other two charges acting on a third charge, q°, will be equal to zero is
x=1.72units
This is further explained below.
What are forces?Generally, The total amount of forces exerted on an item is referred to as its net force. The total of N forces exerted on an item is given in the equation below.
The total force operating on an item, which may include a number of different forces, is known as the net force acting on the object.
The n forces operating on an item are added up in this equation. According to this formula, the amount of net force exerted on an item is equal to the mass times the acceleration of the object.
+3q <------>+11q
[tex]&\frac{1}{4 \pi E v}\left(\frac{3 q}{x^2}-\frac{11 q}{(5-x)^2}\right)=0 \\\\&\frac{3}{x^2}=\frac{11 q}{(5-x)^2} \\&\frac{5-x}{x}=\sqrt{\frac{11}{3}}=1.91 \\\\[/tex]
5-x=1.91 x
=1.715
=1.72units
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