Answer: A) It's a normal force exerted by the floor. It balances out the gravitational force.
The normal force pushes up which means the box doesn't go through the floor. The up and down forces are balance. If the normal force was larger than the gravitational force, then the box would be pushed up and float/jump in the air. But the box is stationary and not moving, so that's why we don't have any acceleration and the forces effectively cancel each other out. In a way you can think of it like a see-saw.
Friction would only come into play if you applied a force and were trying to move the box. Friction counteracts the applied force. If you push the box to the left, then the friction would push to the right. Friction slows down the box and it allows it to not slide forever.
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Is normal force equal to gravity?
The normal force on an object at rest on a flat surface is equal to the gravitational force on that object.
▀▄▀▄Is friction a gravitational force?
Friction is the resistance to motion of one object moving relative to another. It is not a fundamental force, like gravity or electromagnetism. Instead, scientists believe it is the result of the electromagnetic attraction between charged particles in two touching surfaces.
▀▄▀▄Can normal force be greater than gravity?
Can you imagine the situation when Normal force is greater than mg ? Yes. When an additional downward force F is applied to a mass m resting on a horizontal surface, the normal force is FN=F+mg. ... An example is the normal force on an incline plane with an angle of θ due to a mass m.▄▀▄▀▄▀▄
What is the direction of the force you applied?
An applied force is an interaction of one object on another that causes the second object to accelerate or change velocity or direction. The force can be a push, pull, or drag. The resulting direction of an object depends on the relative direction of the force on the object. A force equation is F = ma.
If you have ever baked a cake or bread, you know that the ingredients that combine to make it taste different from the baked food. Why do you think that is?
Answer:
Well we all know that bread and cake taste different. We do this on purpose.
Explanation:
When we make cake we add plenty of sugar to make it the delectable dessert we all know and love while when making bread we focus more on the corn starch and yeast's.
A large research balloon containing 2.00 × 10^3 m^3 of helium gas at 1.00 atm and a temperature of 15.0°C rises rapidly from ground level to an altitude at which the atmospheric pressure is only 0.900 atm. Assume the helium behaves like an ideal gas and the balloon’s ascent is too rapid to permit much heat exchange with the surrounding air.
Required:
a. Calculate the volume of the gas at the higher altitude.
b. Calculate the temperature of the gas at the higher altitude.
c. What is the change in internal energy of the helium as the balloon rises to the higher altitude?
Answer:
a
[tex]T_2 = 276.1 \ K[/tex]
b
[tex]V_2 = 2.13 *10^{3} \ m^3 [/tex]
c
[tex]\Delta U = -1.25 *10^{7} \ J [/tex]
Explanation:
From the question we are told that
The volume of the balloon is [tex]V = 2.00 * 10^3 \ m^3[/tex]
The pressure of helium is [tex]P_1 = 1.00 \ atm= 1.0 *10^{5} \ Pa [/tex]
The initial temperature is [tex]T_1 = 15.0^oC = 288 \ K [/tex]
The pressure of atmosphere is [tex]P_a = 0.900 \ atm[/tex]
Generally the equation representing the adiabatic process is mathematically represented as
[tex]P_1 V_1 ^{\gamma }= P_2 V_2 ^{\gamma }[/tex]
=> [tex]V_2 ^ {\gamma } = \frac{ V_1 ^{\gamma } * P_1 }{P_2}[/tex]
Generally [tex]\gamma[/tex] is a constant with value [tex]\gamma =\frac{5}{3}[/tex] for an ideal gas
So
[tex]V_2 ^ {\frac{5}{3} } = \frac{ ( 2.0 *10^{3}) ^{ \frac{5}{3} } * 1.00 }{0.900}[/tex]
[tex]V_2 = (\sqrt[5]{103.14641852} )^3[/tex]
=> [tex]V_2 = 2.13 *10^{3} \ m^3 [/tex]
Generally the adiabatic process can also be mathematically represented as
[tex]T_1 V_1 ^{\gamma -1 } = T_2 V_2^{\gamma -1 }[/tex]
=> [tex]T_2 = 288 * [\frac{2 * 10^{3}}{ 2.13 *10^{3}} ]^{ \frac{5}{3} -1 }[/tex]
=> [tex]T_2 = 276.1 \ K[/tex]
Generally the ideal gas equation is mathematically represented as
[tex]P_1 V_1 = nRT_1[/tex]
Here R is the gas constant with value [tex]R = 8.314\ J /mol \cdot K[/tex]
[tex]n = \frac{P_1 V_1 }{RT _1}[/tex]
=> [tex]n = \frac{1.0 *10^{5} * 2.0 *10^{3}}{8.314 * 288[/tex]
=> [tex]n = 84362 \ mol[/tex]
Generally change in internal energy i mathematically represented
[tex]\Delta U = n C_v \Delta T[/tex]
Here [tex]C_v[/tex] is the specific heats of gas at constant volume and the value is [tex]C_v = 12.47 J/mol \cdot K[/tex]
[tex]\Delta U = 84362 * 12.47 * [T_2 - T_1 ] [/tex]
[tex]\Delta U = 84362 * 12.47 * [276.1 - 288 ] [/tex]
[tex]\Delta U = -1.25 *10^{7} \ J [/tex]
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Mrs. LaCross leaves school and accidentally leaves her coffee mug on the roof of her car as shown in the picture below.
She was traveling at a constant pace until a student rushes in front of her not using the sidewalks and crosswalks and she had to slam on her brakes. What will happen to her coffee mug?
[ Select ]
a. The mug will move side by side
b. The mug will move backwards
c. The mug will move forward
d. The mug will not move
Answer:
the mug will moveforwards
When we do dimensional analysis, we do something analogous to stoichiometry, but with multiplying instead of adding. Consider the diffusion constant that appears in Fick's first law:
J= -Ddn/dx
In this expression, J represents a flow of particles: number of particles per unit area per second, n represents a concentration of particles: number of particles per unit volume; and x represents a distance. We can assume that they have the following dimensionalities:
[J] = 1/L2T
[n] = 1/L3
[x] = L
Required:
From this, determine the dimensionality of D.
Answer:
The dimension is [tex]D = L ^{2} T^{-1}[/tex]
Explanation:
From the question we are told that
[tex]J = -D \frac{dn}{dx}[/tex]
Here [tex][J] = \frac{1}{L^2 T}[/tex]
[tex][n] =\frac{1}{L^3}[/tex]
[tex][x] = L[/tex]
So
[tex]\frac{1}{L^2 T} = -D \frac{d(\frac{1}{L^3})}{d[L]}[/tex]
Given that the dimension represent the unites of n and x then the differential will not effect on them
So
[tex]\frac{1}{L^2 T} = -D \frac{(\frac{1}{L^3})}{[L]}[/tex]
=> [tex]D = \frac{L^{-2} T^{-1} * L }{L^{-3}}[/tex]
=> [tex]D = L ^{2} T^{-1}[/tex]
Choose which best describes the following argument:
Two flowers of the same species were planted in adjacent plots. The first was fertilized with Miracle-Gro and it flourished. The second was not and it did not flourish, Therefore, Miracle-Gro stimulates plant growth.
a.
Inductive; weak
b.
deductive; sound
c.
Inductive; strong
d.
deductive; valid
Answer: The answer is a
Explanation:
Do electromagnetic waves occur in a continuous spectrum based on their wavelength?
Answer: Yes
Explanation: Because Electromagnetic waves form a continuous spectrum and all types of electromagnetic wave travel at the same velocity through a vacuum (space) or air. The waves that form the electromagnetic spectrum are grouped in terms of their wavelength and their frequency.
1-4 help pls if u know it
Answer:
c,B,a,d i guess i m not sure it is the guessing
when three identical bulbs of 60W,200V rating are connected in series at a 200V supply the power drawn by them will be?
Answer:
P = 180 [w]
Explanation:
To solve this problem we must use ohm's law, which is defined by the following formula.
V = I*R & P = V*I
where:
V = voltage = 200[volts]
I = current [amp]
R = resistance [ohm]
P = power [watts]
Since the bulbs are connected in series, the powers should be summed
P = 60 + 60 + 60
P = 180 [watts]
Now we can calculate the current
I = 180/200
I = 0.9[amp]
Attached is an image where we see the three bulbs connected in series, in the circuit we see that the current is the same for all the elements connected to the circuit.
And the power is defined by P = V*I
we know that the voltage is equal to 200[V], therefore
P = 200*0.9
P = 180 [w]
How long does it take for a Ford Econoline van moving at 39.5 m/s to travel 600 m?
A.
0.0658 s
B.
15.2 s
C.
3.11 s
D.
23700 s
Answer: B. 15.2s
Explanation: 600/39.5 = about 15.2
A dog walks 30. m west, then 40. m east and then 20. m south. What is the
Answer:
90
Explanation:
ark
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Which term identifies the distance between any two adjacent crests on a
wave?
A. Compression
B. Frequency
C. Wavelength
D. Amplitude
Answer:
your answer is wavelength
Explanation:
the the highest service part of a weight is called the crest and the lowest part is the trough the vertical distance between the crest and the trough is the waist height the horizontal disc distance between two adjacent Crest or troughs is known as wavelengths
In a photoelectric effect experiment, light from a blue LED (wavelength = 405 nm) is directed onto a piece of sodium. It is observed that when V = 0.52 volts, the current measured at the collector drops to zero. What is the work function of the sodium? (a) 0.85 eV (b) 2.5 eV (c) 1.6 eV (d) 3.6 eV (e) 0.088 eV 100% What is the highest velocity of an ejected electron, just above the surface of the sodium? (a) 680000 m/s (b) 300000 m/s (c) 430000 m/s 100% Now we decrease the power of the LED, keeping the wavelength fixed. Which of the following statements is true? (a) The maximum velocity of any ejected electrons will decrease. (b) The minimum possible time to eject an electron (relative to when the LED is turned on) will increase.
Answer:
1. (b) 2.5 eV
2. (c) 430000 m/s
3. (a) The maximum velocity of any ejected electrons will decrease.
Explanation:
1)
From Einstein's Photoelectric Equation:
hc/λ = K.E + ∅
∅ = hc/λ - K.E
∅ = hc/λ - eV
where,
e = charge on electron = 1.6 x 10⁻¹⁹ C
V = Stopping Potential = 0.52 volts
h = 6.625 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength = 405 nm = 4.05 x 10⁻⁷ m
∅ = Work Function = ?
Therefore,
∅ = (6.625 x 10⁻³⁴ J.s)(3 x 10⁸ m/s)/(4.05 x 10⁻⁷ m) - (1.6 x 10⁻¹⁹ C)(0.52 volts)
∅ = 4.9 x 10⁻¹⁹ J - 0.832 x 10⁻¹⁹ J
∅ = (4.075 x 10⁻¹⁹ J)(1 eV)/(1.6 x 10⁻¹⁹ J)
∅ = 2.5 eV
therefore, correct answer is"
(b) 2.5 eV
2)
K.E = (1/2)mv² = eV
where,
m = mass of electron = 9.1 x 10⁻³¹ kg
v = speed = ?
therefore,
(1/2)(9.1 x 10⁻³¹ kg)v² = (1.6 x 10⁻¹⁹ C)(0.52 volts)
v = √(0.18 x 10¹² m²/s²)
v = 0.43 x 10⁶ m/s = 430000 m/s
Correct option is:
(c) 430000 m/s
3.
The decrease in power at constant wavelength means decrease in voltage, that results in the decrease of kinetic energy of electrons. So, correct option is:
(a) The maximum velocity of any ejected electrons will decrease.
Based on Kepler's work, which best describes the orbit If a planet around the Sun?
a circle with the Sun at the very center
an ellipse with the Sun at the very center
a circle with the Sun at one edge
an ellipse with the Sun at one focus
Answer:
D. an ellipse with the Sun at one focus
Explanation:
Based on Kepler's work, the orbit of a planet around the Sun is an ellipse with the Sun at one focus.
What is Kepler's law of planetary motion?The sun is at one of the foci of the planets' elliptical orbits around the sun, according to Kepler's first law. Perihelion, the name for the point at which a planet is closest to the sun, and aphelion, the name for the point at which a planet is farthest from the sunThe radius vector extended from the sun to the planet sweeps out equal areas in equal amounts of time, according to Kepler's second law.The square of a planet's period of revolution around the sun in an elliptical orbit is directly proportional to the cube of its semi-major axis, states Kepler's law of periods.Hence according to Kepler's first law of planetary motion, the orbit of a planet around the Sun is an ellipse with the Sun at one focus.
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Four students give their teacher identical apples. Each student sets his or her apple on a different stack of books. Which
apple has the most potential energy?
Answer:
Diagram B.
Explanation:
We'll begin by defining potential energy.
This is given below:
Potential energy is the energy stored in an object due to its position. Mathematically, it is expressed as:
P.E = m × g × h
Where:
P.E is the potential energy.
m is the mass of the object.
g is the acceleration due to gravity.
h is the height to which the object is located.
From:
P.E = m × g × h
We can say that the potential energy (P.E) is directly proportional to the height (h) to which the object is located. This implies that as the height increase, the potential energy of the object will also increase and as the height decrease, the potential energy of the object will also decrease.
Now, considering the question given above, we can see that the height of the object is greater in diagram B. Therefore, The potential energy of the object is greater in diagram B.
Answer:
The answer s B
Explanation:
I WILL MARK BRAINLYEST 40+ POINTS. PLEASE ANSWER!!!
The measure of the amount of atoms (matter) in something.
Group of answer choices
Weight
Mass
Volume
Law of Conservation of Matter (Mass) (LOCM)
Question 310 pts
The reference lines on a graph, i.e. X and Y
Group of answer choices
Coordinates
Line of best fit
Axis
Slope
Question 410 pts
How far apart objects or points are.
Group of answer choices
Inertia
Distance
Net Force
Question 510 pts
Moving from one position to another.
Group of answer choices
Balanced Forces
Traveling
Distance
Question 610 pts
The tendency of things to keep traveling in the same direction at the same speed, unless something stops them.
Group of answer choices
Velocity
Inertia
Gravity
Friction
Answer:
Mass
axis
distance
intertia
Seven little spheres of mercury, each with a diameter of 2 mm. When they coalesce to form a single sphere, how big will it be (i.e. what is its diameter)? How does its surface area compare with the total surface area of the previous Seven little spheres?
Answer:
The total surface area of the seven little spheres is 1.91 times the total surface area of the bigger sphere.
Explanation:
Volume of a Sphere
The volume of a sphere of radius r is given by:
[tex]\displaystyle V=\frac{4}{3}\cdot \pi\cdot r^3[/tex]
The volume of each little sphere is:
[tex]\displaystyle V_l=\frac{4}{3}\cdot \pi\cdot 2^3[/tex]
[tex]V_l=33.51\ mm^3[/tex]
When the seven little spheres coalesce, they form a single bigger sphere of volume:
[tex]V_b=7*V_l=234.57\ mm^3[/tex]
Knowing the volume, we can find the radius rb by solving the formula for r:
[tex]\displaystyle V_b=\frac{4}{3}\cdot \pi\cdot r_b^3[/tex]
Multiplying by 3:
[tex]3V_b=4\cdot \pi\cdot r_b^3[/tex]
Dividing by 4π:
[tex]\displaystyle \frac{3V_b}{4\cdot \pi}= r_b^3[/tex]
Taking the cubic root:
[tex]\displaystyle r_b=\sqrt[3]{\frac{3V_b}{4\cdot \pi}}[/tex]
Substituting:
[tex]\displaystyle r_b=\sqrt[3]{\frac{3*234.57}{4\cdot \pi}}[/tex]
[tex]r_b=3.83\ mm[/tex]
The surface area of the seven little spheres is:
[tex]A_l=7*(4\pi r^2)=7*(4\pi 2^2)=351.86\ mm^2[/tex]
The surface area of the bigger sphere is:
[tex]A_b=4\pi r_b^2=4\pi (3.83)^2=184.33\ mm^2[/tex]
The ratio between them is:
[tex]\displaystyle \frac{351.86\ mm^2}{184.33\ mm^2}=1.91[/tex]
The total surface area of the seven little spheres is 1.91 times the total surface area of the bigger sphere.
If any state tribunal decides a federal question and the litigant has no further remedy within the state court system, from which of the following remedies could the litigant possibly benefit?
A.
a hearing by a US district court
B.
a hearing by a federal court of appeals
C.
a hearing by the US Supreme Court
D.
a Congressional vote
Answer:
B. a hearing by a federal court of appeals
If any state tribunal decides a federal question and the litigant has no further remedy within the state court system, a hearing by a federal court of appeals.
What is appeal by federal courts ?Oral argument in the court of appeals is a prearranged conversation between the judges and the appellate attorneys that focuses on the legal principles at issue. Each party has a limited amount of time usually around 15 minutes to make their case to the judge.
If a litigant loses in a federal court of appeals or in the highest court of a state, they may ask the supreme court to reconsider the case by filing a petition.
Only when a case concerns an extremely significant legal concept or when two or more federal appellate courts have disagreed on how to interpret a statute will the court normally consent to consider it. Additionally, there are a few rare instances where the Supreme Court is mandated by the law to consider an appeal.
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a car travelling at 20m/s comes to a stop in 5 seconds. what distance is required for the car to come to a stop?
A motorcycle traveling south reaches a speed of 38.0 m/s. It then begins uniform negative acceleration and comes to rest after 7.359s. How far did the motorcycle travel in this time?
Answer: 30.641
Explanation: If you get the ave which is 38.0 then the vi which is 7.359
38.0-7.359=30.641/0.0 which is 30.641
1. Wind
A. Definition
B. What Heat Transfer Causes
c. Types
Answer:
B . a heat transfer caused
In your research lab, a very thin, flat piece of glass with refractive index 2.30 and uniform thickness covers the opening of a chamber that holds a gas sample. The refractive indexes of the gases on either side of the glass are very close to unity. To determine the thickness of the glass, you shine coherent light of wavelength λ0 in vacuum at normal incidence onto the surface of the glass. When λ0= 496 nm, constructive interference occurs for light that is reflected at the two surfaces of the glass. You find that the next shorter wavelength in vacuum for which there is constructive interference is 386 nm.
Answer:
λ₀= 495.88 nm
Explanation:
To analyze this constructive interference interference experiment by reflection, let's look at two important aspects:
* when a ray of light passes from a medium with a lower index, they refact to another medium with a higher index, the reflected ray has a phase difference of pyres
* When a beam penetrates a material medium, the wavelength of the radiation changes according to the refractive index of the material.
λₙ = λ₀ / n
when we introduce these aspects in the expression of contributory interference, it remains
2 d sin θ = (m + ½) λ₀ / n
In general, reflection phenomena are measured at an almost normal angle, whereby θ = π/2 and sin θ = 1
2 d = (m +1/2) λ₀/ n
2n d = (m + ½) λ₀
Let's apply this expression to our case
d = (m + ½) λ₀ / 2n
Suppose we measure on the first interference, this is m = 0
d = ½ λ₀ / 2n
let's calculate
d = ½ 496 10⁻⁹ / (2 2.30)
d = 53.9 10-9 m
This is the thickness of the glass, the next wavelength that gives constructive interference is
λ₀ = 2 n d / (m + ½)
let's calculate
λ₀ = 2 2.3 5.39 10-8 / (1 + ½)
λ₀= 4.9588 10-7 m
λ₀= 495.88 nm
What is this car's instantaneous velocity ...
Wait for it ... Wait for it ... ok NOW!!! (in mi/h)
Answer:
it's a Bugatti
Explanation:
I seen pictures and videos of one for what they look like from the inside or the outside
Consider the case where m1 and m2 are both nonzero, and m2>m1. Let T1 be the magnitude of the tension in the rope connected to the block of mass m1, and let T2 be the magnitude of the tension in the rope connected to the block of mass m2. Which of the following statements is true? Consider the case where and are both nonzero, and . Let be the magnitude of the tension in the rope connected to the block of mass , and let be the magnitude of the tension in the rope connected to the block of mass . Which of the following statements is true? T1 is always equal to T2. T2 is greater than T1 by an amount independent of velocity. T2 is greater than T1 but the difference decreases as the blocks increase in velocity. There is not enough information to determine the relationship between T1 and T2.
Answer:
T₂ is greater than T₁ by an amount independent of velocity
Explanation:
This is an exercise on Newton's second law
for block of mass m1
T₁ = m₁ a
for block of mass m²
T₂ = m₂ a
as it indicates that m₂> m₁
the tension T₂> T₁ also we see that in this equation there is no dependence with the velocity, but with the acceleration
the voltage difference does not depend on the speed of the vehicles
When reviewing the answers, the correct one is B
T₂ is greater than T₁ by an amount independent of velocity
In a game of tug of war, a rope is pulled by a force of 182 N to the right and by a force of 108 N to the left. Calculate the magnitude and direction of the net horizontal force on the rope.
Answer:
74 N to the right
Explanation:
the forces are going in opposite horizontal directions, meaning that they are directly opposing each other. this means that you can subtract the force applied in the direction that is greater from the direction that is less to get the net force for the greater direction
this means 182 N - 108 N = 74 N to the right
In a game of tug of war the magnitude and direction of the net horizontal force on the rope is 74 N.
What is force?A force in physics is an effect that has the power to alter an object's motion. An object with mass can change its velocity, or accelerate, as a result of a force. An obvious way to describe force is as a push or a pull. A force is a vector quantity since it has both magnitude and direction.
In a game of tug of war, a rope is pulled by a force of 182 N to the right and by a force of 108 N to the left. The magnitude and direction of the net horizontal force on the rope is,
F = 182 - 108
F = 74 N
The magnitude and direction of the net horizontal force on the rope is 74 N.
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At a tractor pull, one machine has a pull that produces 27,000 joules of power in 3 seconds. How many watts of power did this tractor produce?
3
Answer:
28230 joules
Explanation:
becasue yes
A tiger leaps horizontally froma 7.5 m high rock with a speed of 3.0 m/s. How far from the base of the rock will she land?
Answer:
The tiger will land at 3.71 meters from the base of the rock
Explanation:
Horizontal Motion
When an object is thrown horizontally with a speed vo from a height h, the range or maximum horizontal distance traveled by the object can be calculated as follows:
[tex]\displaystyle d=v\cdot\sqrt{\frac {2h}{g}}[/tex]
The tiger leaps from a height of h=7.5 m with a speed of v=3 m/s. Substituting the values into the formula:
[tex]\displaystyle d=3\cdot\sqrt{\frac {2\cdot 7.5}{9.8}}=3.71\ m[/tex]
The tiger will land at 3.71 meters from the base of the rock
sin20 + cos20 = 1
How?
A person walks 500m due north, turns and walks 300m due west, and finally walks 800m due south. Determine the persons resultant displacement from her starting point.
+500 because North is postiive direction
-300 because if you see it as a graph, left side is negative
-800 because South is downward
500-300-800 = -600
displacement is a vector, meaning it has both DIRECTION and magnitude
(literally the only physics problem i can easily solve lol)
Answer:
[tex]\mid D \mid = 424.26\ m[/tex]
Explanation:
Displacement
Suppose a moving object starts from point A and travels through a determined path to point B. The distance is the sum of all the partial distances traveled, and the displacement is the vector directed from A to B.
The path of the person is shown in the image below. Note the 500 m due north and the 800 m due south produce a distance of 300 m due south. The displacement vector D is the resultant of the whole movement.
To find the magnitude of the displacement, we need to calculate the hypotenuse of a triangle of sides 300 m (already described) and 300 m, marked in red.
The magnitude of D is:
[tex]\mid D \mid = \sqrt{300^2+300^2}[/tex]
[tex]\mid D \mid = \sqrt{90000+90000}[/tex]
[tex]\mid D \mid = \sqrt{180000}[/tex]
[tex]\mid D \mid = 424.26\ m[/tex]
(Use 1.72×10-8 Ωm for the resistivity of copper.) Tries 0/20 For safety, the National Electrical Code limits the allowable amount of current which such a wire may carry. When used in indoor wiring, the limit is 15.0 A for rubber insulated wire of that size. How much power would be dissipated in the wire of the above problem when carrying the maximum allowable current? Tries 0/20 What would be the voltage between the ends of the wire in the above problem? Tries 0/20 What is the current density in the wire when it is carrying the maximum allowable current? (Current density is the current in the wire divided by the cross sectional area of the wire.) Tries 0/20 What is the drift velocity of the electrons when the wire is carrying the maximum allowable current? (The density of electrons in copper is 8.47×1028 m-3.)
Complete Question
A number 14 copper wire has a diameter of 1.628 mm. Calculate the resistance of a 37.0 m long piece of such wire.
(Use 1.72×10-8 ?m for the resistivity of copper.)
For safety, the National Electrical Code limits the allowable amount of current which such a wire may carry. When used in indoor wiring, the limit is 15.0 A for rubber insulated wire of that size. How much power would be dissipated in the wire of the above problem when carrying the maximum allowable current?
What would be the voltage between the ends of the wire in the above problem?
What is the current density in the wire when it is carrying the maximum allowable current? (Current density is the current in the wire divided by the cross sectional area of the wire.)
What is the drift velocity of the electrons when the wire is carrying the maximum allowable current?
(The density of electrons in copper is 8.47×1028 m-3.)
Answer:
a
[tex]R =0.3057 \ \Omega [/tex]
b
[tex]P = 68.78 \ W [/tex]
c
[tex]V = 4.5855 \ V[/tex]
d
[tex]J = 7.205 *10^{6}\ A/m^2 [/tex]
e
[tex]v_d = 0.0005316 \ m/s[/tex]
Explanation:
From the question we are told that
The resistivity of copper is [tex]\rho = 1.72* 10^{-8} \ \Omega \cdot m[/tex]
The current limit is [tex]I = 15 \ A[/tex]
The diameter is [tex]d= 1.628 mm= 0.001628 \ m[/tex]
The length of the wire is [tex]l = 37.0 m[/tex]
The density of electron is [tex]n = 8.47*10^{28} m^{-3}[/tex]
Generally the radius is mathematically represented as
[tex]r = \frac{d}{2}[/tex]
=> [tex]r = \frac{0.001628}{2}[/tex]
=> [tex]r =0.000814 \ m [/tex]
Generally the resistance is mathematically represented as
[tex]R = \frac{\rho * l }{A}[/tex]
Here A is the area which is mathematically represented as
[tex]A = 3.142 * (0.00081)^2[/tex]
=> [tex]A = 2.082 *10^{-6}\ m^2 [/tex]
=> [tex]R = \frac{1.72* 10^{-8} * 37.0 }{2.082 *10^{-6}}[/tex]
=> [tex]R =0.3057 \ \Omega [/tex]
Generally the power dissipated is mathematically represented as
[tex]P = I^2 R[/tex]
=> [tex]P = (15)^2 * 0.3057 [/tex]
=> [tex]P = 68.78 \ W [/tex]
Generally the voltage is mathematically represented as
[tex]V = I * R[/tex]
=> [tex]V = 15 * 0.3057[/tex]
=> [tex]V = 4.5855 \ V[/tex]
Generally the charge density is mathematically represented as
[tex]J = \frac{I}{A}[/tex]
=> [tex]J = \frac{15}{2.082 *10^{-6}}[/tex]
=> [tex]J = 7.205 *10^{6}\ A/m^2 [/tex]
Generally the drift velocity is mathematically represented as
[tex]v_d = \frac{I}{ n * A * e}[/tex]
Here e is the charge on an electron with value [tex]e = 1.60 *10^{-19} \ C[/tex]
So
[tex]v_d = \frac{15}{ 8.47*10^{28} * 2.082 *10^{-6} * 1.60 *10^{-19} }[/tex]
=> [tex]v_d = \frac{15}{ 8.47*10^{28} * 2.082 *10^{-6} * 1.60 *10^{-19} }[/tex]
=> [tex]v_d = 0.0005316 \ m/s[/tex]
A cube with sides 12 cm is submerged in water to a depth of 30 cm. Given density of water is 1000 kg/m3. Calculate the pressure at the bottom surface of the cube due to water.
Answer:
P=2940 Pa
Explanation:
Given that,
Side of a cube, a = 12 cm
It is submerged to depth of 30 cm
The density of water, d = 1000 kg/m^3
We need to find the pressure at the bottom surface of the cube. We know that the pressure exerted is given by :
[tex]P=d gh\\\\P=1000\ kg/m^3\times 9.8\ m/s^2\times 0.3\ m\\\\P=2940\ Pa[/tex]
So, 2940 Pa of pressure is exerted at the bottom surface of the cube due to water.