Answer:
Explanation: The chemical action that occurs in the cell while the current is flowing causes hydrogen bubbles to form on the surface of the anode. This action is called POLARIZATION. Some hydrogen bubbles rise to the surface of the electrolyte and escape into the air, some remain on the surface of the anode. If enough bubbles remain around the anode, the bubbles form a barrier that increases internal resistance. When the internal resistance of the cell increases, the output current is decreased and the voltage of the cell also decreases.
A cell that is heavily polarized has no useful output. There are several methods to prevent polarization or to depolarize the cell.
One method uses a vent on the cell to permit the hydrogen to escape into the air. A disadvantage of this method is that hydrogen is not available to reform into the electrolyte during recharging. This problem is solved by adding water to the electrolyte, such as in an automobile battery. A second method is to use material that is rich in oxygen, such as manganese dioxide, which supplies free oxygen to combine with the hydrogen and form water.
A third method is to use a material that will absorb the hydrogen, such as calcium. The calcium releases hydrogen during the charging process. All three methods remove enough hydrogen so that the cell is practically free from polarization.
LOCAL ACTION
When the external circuit is removed, the current ceases to flow, and, theoretically, all chemical action within the cell stops. However, commercial zinc contains many impurities, such as iron, carbon, lead, and arsenic. These impurities form many small electrical cells within the zinc electrode in which current flows between the zinc and its impurities. Thus, the chemical action continues even though the cell itself is not connected to a load.
Local action may be prevented by using pure zinc (which is not practical), by coating the zinc with mercury, or by adding a small percentage of mercury to the zinc during the manufacturing process. The treatment of the zinc with mercury is called amalgamating (mixing) the zinc. Since mercury is many times heavier than an equal volume of water, small particles of impurities weighing less than mercury will float to the surface of the mercury. The removal of these impurities from the zinc prevents local action. The mercury is not readily acted upon by the acid. When the cell is delivering current to a load, the mercury continues to act on the impurities in the zinc. This causes the impurities to leave the surface of the zinc electrode and float to the surface of the mercury. This process greatly increases the storage life of the cell.
A hammer strikes a nail with a 10N force for .01 seconds. Calculate the impulse of the hammer
Answer:
Impulse = 0.1 Kgm/s
Explanation:
Given the following data;
Force, F = 10N
Time, t = 0.01 seconds
To find impulse
An impulse can be defined as the net force acting an object for a very short period of time.
Mathematically, impulse is given by the formula;
Impulse = force * time
Substituting into the equation, we have;
Impulse = 10 * 0.01
Impulse = 0.1 kgm/s
Therefore, the impulse of the hammer is 0.1 kilogram meter per seconds.
The impulse of the hammer is 0.1 Ns.
To solve the given problem we need to use the formula for calculating impulse.
Impulse: This can be defined as the product of force and time on a body.
The formula of impulse is given below.
I = Ft....................... Equation 1
Where :
I = Impulse of the harmerF = Force on the nailt = timeFrom the question,
Given:
F = 10 Nt = 0.01 sSubstitute these values into equation 1
I = 10(0.01)I = 0.1 NsHence, The impulse of the hammer is 0.1 Ns.
Learn more about force here: https://brainly.com/question/13370981
ANSWER ALL QUESTIONS and show your work ON THE ATTACHMENT AWARD 50 pts if you don’t know the answer to all of them I have posted them individually so I can still mark you brainlessly (however you spell the darn thing)
Answer:
the velocity is 210 - hq squared which equals to 14
A pail in a water well is hoisted by means of a frictionless winch, which consists of a spool and a hand crank. When Jill turns the winch at her fastest water-fetching rate, she can lift the pail the 28.0 m to the top in 11.0 s. Calculate the average power supplied by Jill's muscles during the upward ascent. Assume the pail of water when full has a mass of 7.30 kg.
Answer:
182.28 W
Explanation:
Here ,
m = 7.30 Kg
distance , d= 28.0 m
time , t = 11.0 s
average power supplied = change in potential energy/time
average power supplied = m×g×d/time
average power supplied = 7.30×9.81×28/11
average power supplied = 182.28 W
the average power supplied is 182.28 W
As an astronaunt travels from the surface of the earth to a postion that is four times
as far away from the center of the earth, the astronaut's
a) mass decreases
b)
mass remains the same
c) weight increases
d) weight remains the same
Answer: mass remains the same
Explanation:
My teacher gave me the answer
As an astronaut travels from the surface of the earth to a position that is four times as far away from the center of the earth, the astronaut's:
B. Mass remains the sameAccording to the given question, we can see that an astronaut is on a journey to a new location which is four times further from the center of the earth. We need to find out if there is a change to the mass of the astronaut.
As a result of this, we can see that the mass of the astronaut remains the same as he travels to a position which is four times further from the center of the earth, because the gravitational forces are the same.
Therefore, the correct answer is option B
Read more here:
https://brainly.com/question/17301500
Parent: My son spends three hours on homework every night. He has no time to see his friends. He has no time to relax. We are watching him turn into a homework machine instead of a human being.
Answer:
this is a homework helping website I don't know If I can help you with this problwm
What is the water cycle ?
Answer:
The water cycle shows the continuous movement of water within the Earth and atmosphere. ... Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow. Water in different phases moves through the atmosphere (transportation).
Explanation:
It's the water cycle.
A 200 g air-track glider is attached to a spring. The glider is pushed 10.0 cm against the spring, then released. A student with a stopwatch finds that 10 oscillating take 12.0 s. What is the spring constant?
Answer:
5.5N/m
Explanation:
Calculation for What is the spring constant
First step is to calculate the time period
T = 12 second/10
T = 1.2 second
Now let calculate the spring constant using this formula
k=4π²m/T²
Where,
m=0.2kg
T=1.2second
k represent spring constant=?
Let plug in the formula
k=4π²×0.2kg/(1.2)²
k=39.48×0.2kg/1.44
k=7.90/1.44
k=5.48N/m
k=5.5N/m ( Approximately)
Therefore the spring constant will be 5.5N/m
Which example provides a complete scientific description of an object in motion?
(A) The hiker followed the north trail a distance of two kilometers in thirty minutes
(B) The tiger had to run at 50 kilometers per hour across the field to catch the zebra
(C) The hockey player sent the puck flying toward the north goal to score the winning point
(D) The vibration of the jackhammer broke through the south-facing rock in under 10 seconds
Answer:
C
Explanation:
it explains how an object that was in motion continued motion after the force
A circular wire loop lies inside a region of space containing a magnetic field. The direction of the magnetic field is out of the screen and parallel to the central axis of the loop. The magnitude of the magnetic field increases as a function of time. A circular loop oriented parallel to the plane of the screen lies inside a region containing magnetic field B. The field is directed out of the screen and is increasing. What is the direction of the induced current in the loop
Answer:
clockwise
Explanation:
According to the law given by Lenz, known as the Lenz law, it is said that a current induced in the circuit which is due to the change in the magnetic field and is so directed so as to oppose the change in the flux and to apply a force in the opposite direction if the force.
Here, as the magnetic field is directed out of the screen, the current flows in the direction which is clockwise in the loop and it opposes the increasing magnetic field.
The clockwise induced current will produce magnetic field in to the screen.
Two locomotives approach each other on parallel track. Each has speed of 95 km/h with respect to the ground.If they are initially 8.5 km apart. How long will it take before they reach each other?
Answer:
It will take 2.68 minutes for them to reach each other.
Explanation:
We use the two following kinematic equations, making the final position the same (for the moment they meet each other):
locomotive 1 --> [tex]x_f=v*t[/tex]
locomotive 2 --> [tex]x_f=8.5\,-\,v*t[/tex]
we make the two xf equal, and solve for the time (t) using v = 95 km/h:
[tex]95*t=8.5-95*t\\2*95*t=8.5\\t=8.5/(190)\\t = 0.0447\,\,hours[/tex]
converting the hours into minutes by multiplying this value times 60;
t = 2.68 minutes
A bicyclist is riding a constant speed 62.0 seconds for 200. meters what is his average speed
Answer:
Explanation::
A ball weighing 60 N is swinging like a pendulum at the end of a 6.0 m rope. As the ball swings through its lowest point, its speed is measured at 5.0 m/s. What is the tension in the rope at this point?
A. 58.6 N
B. 85.4 N
C. 90.2 N
D. 97.3 N
Answer:
85.4 N
Explanation:
Weight of the ball, W = 60 N
W = mg, m is mass
m = W/g
m = 60/9.8 = 6.12 kg
Length of a rope, r = 6 m
Speed, v = 5 m/s
We need to find the tension in the rope at this point. Tension is equal to the centripetal force It is given by :
[tex]F=\dfrac{mv^2}{r}+mg\\\\F=\dfrac{6.12\times (5)^2}{6}+60\\\\=85.5\ N[/tex]
So, the correct option is (b) " 85.4 N".
It is now 9:11 a.m. but when the bell rings at 9:12 a.m. Susie will be late for Mrs. Garner's U.S. History class for the 3rd time this week. She must get from one side of the school to the other by hurrying down three different hallways. She runs down the first hallway (D-Hall), a distance of 47.0 meters. The second hallway (C-Hall) is filled with students, and she covers its 63.0 m length quickly. The final hallway (B- Hall) is empty, and Susie sprints its 76.0 m length. How fast does Susie need to go to make it to class on time (Hint: Calculate the total distance. Then calculate her total average speed rounded to the nearest tenths in meters/seconds.)?
Answer:
3.1 m/s
Explanation:
The total distance she has to run is the addition of the three lengths:
47 + 63 + 76 = 186 meters.
She needs to cover it one minute (60 seconds). Therefore her speed must be:
186 m / 60 s = 3.1 m/s
How fast should a rocket ship move for its mass to be dilated to 167% of its rest
mass?
Answer:
The two forces acting on rockets at the moment of launch are the thrust upwards and the weight downwards. Weight is the force due to gravity and is calculated (at the Earth’s surface) by multiplying the mass (kilograms) by 9.8.The resultant force on each rocket is calculated using the equation resultant force = thrust – weight.
Hopefully, this answer helps you! :)
in the figure if coefficient of friction between block and surface is 0.2 then find acceleration produced by the resultant force acting on the block (take g= 10 m/s²)
☃ First of all we have to calculate frictional force by using below equation :
→ F = μR
→ F = 0.2 × 5 × 10
→ F = 10 N
Hence,the frictional force (F) is 10 N.☃ But we know that frictional force is acting on opposite direction of the motion :
⇏Net force = 15 - 10
⇏Net force = 5 N
Hence,the net force is 5 N.☃ By using Newton's second law we get :
Let the required acceleration produced by the block be 'a'.➝ Force = mass × acceleration
➝ 5 = 5 × a
➝ a = 5 ÷ 5
➝ a = 1 m/s²
Hence,the acceleration produced by the resultant force acting on the block is 1 m/s².From the anatomical position, the digits are ____ to the brachium.
A. Anterior
B. Inferior
C. Superior
D. Medical
Isaac Newton discovered the three laws of motion. Which example best illustrates Newton's third law of motion, which describes action and reaction forces?
O a rocket takes off from the ground
O a book slides forward on a seat when the car stops
O a heavier ball falls at the same speed as a lighter ball
O a vehicle rounds a curve and changes its acceleration
The third law of motion defined the action and reaction force that the heavy ball should be fall at the same kind of the speed.
What is third law of motion?It defined that at the time when the two bodies should be interacted so here the forces should be applied to one another that should be equivalent to the magnitude also the direction should be opposite.
Also, we can called as the action law and the reaction.
Therefore, we can conclude that the third option is correct.
Learn more about motion here: https://brainly.com/question/12742278
A race car starts from rest and accelerates down a track at a rate of 3.0 m/s2
How fast is the car moving after 10 seconds?
30 m/s
Explanation:We are given:
Initial Velocity (u) = 0 m/s
Acceleration of the Car (a) = 3 m/s²
Time Interval (t) = 10 seconds
Speed of the Car After 10 seconds:
From the First equation of motion:
v = u + at
replacing the given values
v = 0 + (3)(10)
v = 30 m/s
Hence, the car is moving at a velocity of 30 m/s after 10 seconds
A box of weighing 60N is placed on the ground. The bottom of the box measures 2m by 1m. What is the pressure on the ground? *
Answer:
pressure=force/area
p=60N/(2m×1m)
=35N/M
5. The wire in consists of two segments of different diameters but made from the same metal. The current in segment 1 is I1. a. (1 pt) Compare the currents in the two segments. That is, is I2 greater than, less than, or equal to I1? Explain. b. (1 pt) Compare the current densities J1 and J2 in the two segments. c. (1 pt) Compare the electric field strengths E1 and E2 in the two segments. d. (1 pt) Compare the drift speeds vd1 and vd2 in the two segments.
Answer:
hello your question is incomplete attached below is the complete question
answer :
a) I1 = I2
b) J1 > J2
c) E 1 > E2
d) ( vd1 ) > ( vd2 )
Explanation:
a) The currents in the two segments are the same i.e. I1 = I2 and this is because the segments are connected in series
b) Comparing the current densities J1 and J2 in the two segments
note : current density ∝ 1 / area
The area of the second segment is > the area of first segment therefore
J1 > J2
J1 ( current density of first segment )
J2 ( current density of second segment )
c) Comparing the electric field strengths E1 and E2
note : electric field strength ∝ current density
since current density of first segment is > current density of second segment and conductivity of the materials are the same hence
E 1 > E2
d) Comparing the drift speeds Vd1 and Vd2
( vd1 ) > ( vd2 )
this because ; vd ∝ current density
Currents in the two segments are equal. Current densities, electric field strengths and drift speeds of the first segment are greater than the second segment.
What is electric field?The electric field is the field, which is surrounded by the electric charged. The electric field is the electric force per unit charge.
The wire in consists of two segments of different diameters but made from the same metal.
a. Compare the currents in the two segments.The current in segment 1 is [tex]I_1[/tex] and the current in segment 2 is [tex]I_2[/tex]. As, the segments are connected in the series connection. Thus, the value of both the currents will be equal.
[tex]I=I_1=I_2[/tex]
b. Compare the current densities J1 and J2 in the two segments.The current density is total electric current which is flowing in a unit cross sectional area. Current density is inversely p[proportional to the cross sectional area.
The cross-sectional area of the second segment is greater than the first one as shown in the image attached below.
Thus, the current densities of first segment will be J1 greater than the current density of second segment J2.
[tex]J_1 > J_2[/tex]
c. Compare the electric field strengths E1 and E2 in the two segments.The current density of the first segment is greater than the second one. Thus, the electric field of the first segment will also be greater than the second one for the same material.
[tex]E_1 > E_2[/tex]
d. Compare the drift speeds vd1 and vd2 in the two segments.Current density is directly proportional to the drift velocity. As the current densities of first segment is greater than the current density of second segment.Therefore, there drift speed,
[tex]v_{d1} > v_{d2}[/tex]
Hence, the currents in the two segments are equal. Current densities, electric field strengths and drift speeds of the first segment are greater than the second segment.
Learn more about electric field here;
https://brainly.com/question/14372859
an effort force 40n is applied to a screwdriver to pry the lid off of a can of pain. the screwdriver applies 100n of force to the lid. what is the MA of the screwdriver?
Answer:
MA = 2.5
Explanation:
Given that,
Effort force applied to a screwdriver to pry the lid off of a can= 40 N
The screwdriver applies 100n of force to the lid = 100 N
We need to find the mechanical advantage of the screwdriver. Mechanical advantage of a machine is given by the ratio of load to the effort.
m = load/effort
= 100/40
= 2.5
Hence, the MA of the screwdriver is 2.5
What are the effects of hot rolling on the metal grain structure?
Answer:Mark me as the brainliset
Explanation:The rollers impart compression stresses, while squeezing the metal. These results in changes of grains, grain fragmentation, and lattice distortion. In hot rolling the coarse grains are converted into smaller grains. Care has been taken that the correct range of temperature is maintained during the process.
A chimpanzee climbs a vine up and to the right for a total displacement of 50 m 50m50, start text, m, end text that makes a 60 ° 60°60, degree angle from the ground. What was the horizontal displacement of the chimpanzee in m mstart text, m, end text?
Answer:
25m
Explanation
Let the horizontal displacement formula be expressed as;
Dx = Dcos theta
theta is the angles subtended by the displacement
Given
D = 50m
theta = 60°
Required
horizontal displacement of the chimpanzee
Substitute into the formula
Recall that: Dx = Dcos theta
Dx = 50cos60°
Dx = 50(0.5)
Dx = 25m
Hence the horizontal displacement of the chimpanzee is 25m
what are the importance of informal education?
Answer:
Informal education is important because it can help individual to learn how to react and control situations.
It help individual to improve on its existing knowledge, new skills or ideas. This kind of education can happen any where and it can add values to the learner.
Explanation:
Informal education is a type of education that is learned from different life experiences, happenings outside a structured curriculum.
Informal education is important because it can help individual to learn how to react and control situations.
It help individual to improve on its existing knowledge, new skills or ideas. This kind of education can happen any where and it can add values to the learner.
explain and derive the equation for capillary action in the phenomenon of surface tension
Answer:
Explanation:Capillary action is the ability of a liquid to flow in narrow spaces without the assistance of, ... This article is about the physical phenomenon. ... If the diameter of the tube is sufficiently small, then the combination of surface tension (which is caused by cohesion ... They derived the Young–Laplace equation of capillary action.
True/False: The core, mantle, and crust explanation for the Earth's layers is outdated and now we use the 5 layer explanation. *
Answer:
False
Explanation:
We still use the old way. It's easier to understand the old way, and its NOT outdated.
Consider a star that is a sphere with a radius of 6.32 108 m and an average surface temperature of 5350 K. Determine the amount by which the star's thermal radiation increases the entropy of the entire universe each second. Assume that the star is a perfect blackbody, and that the average temperature of the rest of the universe is 2.73 K. Do not consider the thermal radiation absorbed by the star from the rest of the universe. J/K
Answer:
The value is [tex]\Delta s = 8.537 *10^{25 } \ J/K[/tex]
Explanation:
From the we are told that
The radius of the sphere is [tex]r = 6.32 *10^{8} \ m[/tex]
The temperature is [tex]T_x = 5350 \ K[/tex]
The average temperature of the rest of the universe is [tex]T_r = 2.73 \ K[/tex]
Generally the change in entropy of the entire universe per second is mathematically represented as
[tex]\Delta s = s_r - s_x[/tex]
Here [tex]s_r[/tex] is the entropy of the rest of the universe which is mathematically represented as
[tex]s_r = \frac{Q}{T_r}[/tex]
Here Q is the quantity of heat radiated by the star which is mathematically represented as
[tex]Q = 4 \pi * r^2 * \sigma * T^4_x[/tex]
Here [tex]\sigma[/tex] is the Stefan-Boltzmann constant with value
[tex]\sigma = 5.67 * 10^{-8 }W\cdot m^{-2} \cdot K^{-4}.[/tex]
=> [tex]Q = 4 \pi * (6.32*10^{8})^2 * 5.67 * 10^{-8 } * 5350 ^4[/tex]
=> [tex]Q = 2.332 *10^{26} \ J[/tex]
So
[tex]s_r = \frac{2.332 *10^{26}}{2.73}[/tex]
=> [tex]s_r = 8.5415 *10^{25}\ J/K[/tex]
Here [tex]s_x[/tex] is the entropy of the rest of the universe which is mathematically represented as
[tex]s_x = \frac{Q}{T_x}[/tex]
=> [tex]s_x = \frac{2.332 *10^{26} }{5350}[/tex]
=> [tex]s_x = 4.359 *10^{22} \ J/K[/tex]
So
[tex]\Delta s = 8.5415 *10^{25} - 4.359 *10^{22}[/tex]
=> [tex]\Delta s = 8.537 *10^{25 } \ J/K[/tex]
This question involves the concepts of entropy and the thermal radiation
The entropy of the entire universe is increased by "8.41 x 10²⁵ J/k
".
The increase in entropy is given as follows:
[tex]\Delta s = s-s_T[/tex]
where,
Δs = increase in entropy = ?
σ = Stefan-Boltzman's constant = 5.67 x 10⁻⁸ W/m².k⁴
A = surface area = 4πr² = 4π(6.32 x 10⁸ m)² = 5.01 x 10¹⁸ m²
Tr = Absolute temperature of the star = 5350 K
T = absolute temperature of the rest of the universe = 2.73 k
Q = thermal radiation energy
Q = [tex]\sigma A T_r^4=(5.67\ x\ ^{-8}\ W/m^2.k^4)(5.01\ x\ ^{18}\ m^2)(5350\ k)^4=2.3\ x\ 10^{26}\ J[/tex]
s = entropy of the universe = [tex]\frac{Q}{T}=\frac{2.3\ x\ 10^{26}\ J}{2.73 k}=8.42\ x\ 10^{25}\ J/k[/tex]
[tex]s_T[/tex] = entropy of the star = [tex]\frac{Q}{T_r}=\frac{2.3\ x\ 10^{26}\ J}{5350\ k}=4.3\ x\ 10^{22}\ J/k[/tex]
Therefore,
Δs = 8.42 x 10²⁵ J/k - 4.3 x 10²² J/k
Δs = 8.41 x 10²⁵ J/k
Learn more about entropy here:
https://brainly.com/question/13146879?referrer=searchResults
Which best describes the law of conservation of mass?
O The coefficients in front of the chemicals in the reactants should be based on the physical state of the products,
O Products in the form of gases are not considered a part of the total mass change from reactants to products
O When reactants contain both a solid and a liquid, the solid counts toward the overall mass and the liquid does not
O The mass of the reactants and products is equal and is not dependent on the physical state of the substances.
Explanation:
The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.
A 2800 kg speedboat starting from rest attains a speed of 16 m/s in 8.0 s as a combination of 1200 N of air resistance and water drag act on the boat. How much power is being expended by speedboat at the maximum speed?
Answer:
For me
Explanation:
first of all
find the distance=speed×time
16×8=128
power= workdone /time
power=force×distance/time
power=1200×128/8
power=153600/8
powere=19200
a boy pushing a 200kg object on the floor it begins from rest and reaches 20 m/s² in 10 minutes, what is it's acceleration?
Answer:
I hope the above pic helps you mate
I will always help you understanding your assingments
have a great day
#Captainpower:)