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 particle performing circular motion along the path of radius 2 metre with linear acceleration 5 metre per second square find its angular acceleration
Answer:
What is the question though?
Explanation:
You're driving a bumper car at a circus at
18 m/sec, and you hit another car that's at
rest. If you end up going at 6.0 m/sec, what
is the final speed of the other car, given
that both cars have 100.0 kg mass, you
have 80.0 kg mass, and the other person
has a mass of 70.0 kg?
Answer:
PLEASE MARK AS BRAINLIEST!!
Explanation:
ANSWER IS IN THE IMG BELOW
1. If a 4000 kg rocket reaches 7,000 m/s in 8 minutes after blastoff, what is its acceleration?
2. What force is being applied to the rocket?
3. What is the rocket's potential energy when it is 12 km off the ground?
(Hint - Change kilometers to meters)
4. If the rocket were to fall from the 12 km height, what would be its speed right before hitting the ground? (assume no air resistance)
+ answer all the questions plz
Answer:
I guess the Ans for second one is gravitational force
What is the turning effect of a force?
A force may cause an object to turn about a pivot. The turning effect of a force is called the moment of the force. Moments act about a pivot in a clockwise or anticlockwise direction.
Answer:
A force may cause an object to turn about a pivot. The turning effect of a force is called the moment of the force. Moments act about a pivot in a clockwise or anticlockwise direction.
Explanation:
Need help ASAP plsss
Write 5-6 sentences about
:how do parachutes work ??
A ripcord system pulls a closing pin, which releases a spring-loaded pilot chute, and opens the container; from which the parachute comes out.
If a skydiver is unable to open her/his parachute, an automatic activation device will automatically open the parachute.
A parachute works by forcing air into the front of it and creating a structured 'wing' under which the canopy pilot can fly. Parachutes are controlled by pulling down on steering lines which change the shape of the wing, cause it to turn, or to increase or decrease its rate of descent.
А
Each sentence describes potential and kinetic energy
at various locations on a slide. Complete each
statement by selecting the position of the object on the
slide.
An object at position has all kinetic energy
An object at position has all potential energy
An object at position has about half potential energy
and half kinetic energy.
B
с
Answer:
C. A. B.
Explanation:
Credit to Lainey in the comments for the answer!
Answer:
1] C
2] A
3] B
Explanation:
A small sphere of mass m and charge –q is released from rest at point T. If the electric potentials at points S and T are VS and VT, respectively, what is the speed of the sphere when it reaches point S? Ignore the effects of gravity.
(A) 2q/m(Vs + VT)
(B) 4q/m(Vs + VT)
(C) q/2m(Vs - VT)
(D) q/2m (Vs + VT)
(E) 2q/m(Vs - VT)
Answer:
(E) √[2q/m(Vs - VT)]
Explanation:
Since the charge -q moves from VT to VS, the potential difference is VT - VS.
The work done in moving the charge q across a potential difference V is given by W = qV.
Now, the work done in moving the charge -q across that potential difference VT - VS is thus W = -q(VT - VS) = -q[-(VS - VT)] = q(VS - VT). This work equals the sphere's kinetic energy and kinetic energy equals K = 1/2mv² where m = mass of sphere and v = speed of sphere.
So, K = W
1/2mv² = q(VS - VT)
v² = 2q/m(VS - VT)
taking square root of both sides, we have
v = √[2q/m(Vs - VT)]
name three characteristics of sound
1. express the following in proper SI form using the appropriate prefixes. a. 52500000 m b. 1000 g c. 2435200000
Answer:
a
[tex]L = 5.25*10^{7} \ m[/tex]
b
[tex]m = 1 \ kg[/tex]
c
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
Explanation:
From the question we are told that
Length is L = 52500000 m
Mass is
Time is 2435200000 minutes
Generally the proper SI for length is meters ,
Now converting the given length to proper SI form using the appropriate prefixes we have that
[tex]L = 5.25*10^{7} \ m[/tex]
Generally the proper SI for mass is kilograms
converting grams to kilograms , we have
[tex]m =\frac{1000}{1000 }[/tex]
=> [tex]m = 1 \ kg[/tex]
Generally the proper SI for time is seconds
converting minutes to seconds , we have
[tex]t = 24352000000* 60[/tex]
=> [tex]t = 146112000000 \ s[/tex]
Now converting to the proper SI form using the appropriate prefixes
[tex]t = 1.46112000000 *10^{11} \ s[/tex]
Which is an example of a chemical change?
frying an egg
boiling water
melting butter
chopping onions
Answer:
Frying an Egg
Explanation:
When chemical bonds are broken or formed, new particles are created. Therefore, frying an egg is a chemical change because it results in the formation of new particles.
Frying an egg is an example of chemical change. Therefore, option (A) is correct.
What is the chemical change?A chemical change can be described as a change in which a chemical substance is converted into one or more new types of substances. Chemical changes occur through chemical reactions that result in substances with different properties.
Chemical changes are irreversible in nature and are also called permanent changes in which an entirely new substance is formed. We have three kinds of chemical change organic, biochemical and inorganic.
While frying an egg, the egg changes from a fluid to a strong one. The egg changes from a fluid protein into a strong mass. Actually, the strands of protein extend, permitting the protein to denature by breaking the chemical bonds and formation of a new product.
Therefore, Frying an egg is a chemical change while boiling water, melting butter, and chopping onions are physical changes.
Learn more about chemical change, here:
brainly.com/question/23693316
#SPJ6
Choose all correct sentences Group of answer choices The power is maximum when the value of the impedance is greater than the value of the resistance. Resonance occurs when omega squared space equals 1 divided by space L C At resonance, the power is maximum and the impedance is minimum. At resonance, R squared space equals space (X subscript L minus X subscript c )squared The impedance Z is always larger than the resistance R.
Answer:
True b and c
Explanation:
In an RLC circuit the impedance is
[tex]Z = \sqrt{[R^{2} + ( (wL)^{2} + (\frac{1}{wC})^{2} ] }[/tex]
examine the different phrases..
a) False. The maximum impedance is the value of the resistance
b) True. Resonance occurs when
(wL)² + (1 / wC)² = 0
w² = 1 / LC
c) True. In resonance the impedance is the resistive part and the power is maximum
d) False. In resonance the inductive and capacitive part cancel each other out
e) False. The impedance is always greater outside of resonance, but at the resonance point they are equal
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:)
Suppose three forces are acting on a model rocket launching into the air. The force of gravity is 1.2 N acting downward. The rocket engine has a force of 12.3 N acting at an angle of 65⁰ above the horizontal to the right. The wind pushes the rocket with a force of 2.5 N to the left. Find the magnitude and direction of the resultant force on the rocket.
Please answer!!! Offering 50 points for answer and explanation
Answer:
can you include a picture
Decompose the forces acting on the rocket in horizontal and vertical components.
• net horizontal force:
∑ F = (12.3 N) cos(65°) - 2.5 N ≈ 2.7 N
(notice we're taking "to the right" to be the positive direction)
• net vertical force:
∑ F = (12.3 N) sin(65°) - 1.2 N ≈ 9.9 N
The resultant force then has magnitude
√((2.7 N)² + (9.9 N)²) ≈ 10.3 N
Since the horizontal and vertical components of the resultant are both positive, it points at an angle between 0° and 90° from the positive horizontal, so that
tan(θ) ≈ (9.9 N) / (2.7 N) ≈ 3.69
===> θ ≈ arctan(3.69) ≈ 75°
According to The Flash, The heroes top speed is Mach 3.3, or 2,500 miles per hour. How
long would it take for him to run around the planet? (circumference of the earth is
roughly 25,000 miles) *
Answer:
nearly 2 days or less hes fast but not that fast
Explanation:
but maybe he can run it in five minutes
calculate the force necessary to keep a mass of 2 kg moving on a circular path of radius 0.2 m with a period of 0.5 second. what is the direction of this force
(a) Calculate the linear acceleration of a car, the 0.220-m radius tires of which have an angular acceleration of 11.0 rad/s2. Assume no slippage.
Answer:
The value is [tex]a_t = 2.42 \ m/s^2[/tex]
Explanation:
From the question we are told that
The radius of the tires is [tex]r = 0.22 \ m[/tex]
The angular acceleration is [tex]\alpha = 11.0 \ rad/s^2[/tex]
Generally the linear acceleration is mathematically represented as
[tex]a_t = r * \alpha[/tex]
=> [tex]a_t = 0.22 * 11[/tex]
=> [tex]a_t = 2.42 \ m/s^2[/tex]
Can you help with this question please thanks
Answer:
no .the blue runner began 16 m ahead of the red runner
A particle starts from rest and moves with a constant acceleration. It travels the first 16 m in 4 s.
The time (in second) at which the velocity of the particle becomes. 8. m/s is:
a) 3
b) 4
c) 5
d) 6
e) 7
Answer:
B
Explanation:
What is the resistance of a wire with "p" of .25, a length "L" of 11.2, and an area "A" of 1.26?
Answer:
Resistance = 2.2 Ohms.
Explanation:
Given the following data;
Resistivity, P = 0.25
Length, L = 11.2
Area, A = 1.26
To find the resistance.
Resistance is given by the formula below;
Resistance = PL/A
Substituting into the equation, we have;
Resistance = (0.25*11.2)1.26
Resistance = 2.8/1.26
Resistance = 2.2 Ohms.
Therefore, the resistance of the wire is 2.2 Ohms.
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.A bicyclist is riding a constant speed 62.0 seconds for 200. meters what is his average speed
Answer:
Explanation::
Some metals have a molecular structure that makes them good conductors. Explain how understanding this relationship can help engineers make more powerful batteries.
Answer:
Explained below.
Explanation:
Conductors can be defined as materials that permit electricity to flow through them easily.
Now, metals have a molecular structure that makes them good conductors because electrons in the atoms of these conductors tend to move freely from one atom to the other. So a majority of metals make good conductors because these metals tend to hold their electrons loosely. In short, it can help engineers make powerful batteries because then it means that they are capable of giving much more electrical energy since nowadays, advanced batteries make use of ion charges for the batteries.
what is the difference between alcoholic and Mercury thermometer based on their function?
A bowling ball weighing 71.2 N is swinging like a pendulum at the end of a 3.8 m rope. As the ball swings through its lowest point, its speed is measured at 4.2 m/s. What is the magnitude and direction of the acceleration of the ball at this point?
At its lowest point, the ball feels a downward force due to its weight of 71.2 N and an upward force of tension from the rope. Its motion is circular, so that the net radial acceleration is felt upward toward the center of the circle.
With a tangential speed of 4.2 m/s at the lowest point, its radial acceleration has magnitude
a = (4.2 m/s)² / (3.8 m) ≈ 4.6 m/s²
A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. All parts are 4 points each.
Complete Question
1 a A little girl pushes a 5.0 kg toy baby stroller at constant speed 7.0 m across the floor. She pushes on the handle with a force of 40 N at an angle of 30o with the horizontal. How much work is done by the girl on the wagon?
1b A farmhand pushes 20 ㎏ bale of hay 4m across the floor of the barn if she exerts a horizontal force of 60 N on the hay, how much work is done? (5 pts)
All parts are 4 points each
Answer:
1a
[tex]W = 242.5 \ J[/tex]
1b
[tex]W = 240 \ J[/tex]
Explanation:
Considering question a
From the question we are told that
The mass of the toy baby stroller is [tex]m = 5.0 \ kg[/tex]
The distance covered is [tex]d = 7.0\ m[/tex]
The force the girl applies on the handle is [tex]F = 40 \ N[/tex]
The angle at which this force is applied is [tex]\theta = 30^o[/tex]
Generally the workdone is mathematically represented as
[tex]W = F_x * d[/tex]
Here [tex]F_x[/tex] is the force along the horizontal axis , this is mathematically represented as
[tex]F_x = F cos (\theta )[/tex]
=> [tex]F_x = 40 * cos(30 )[/tex]
=> [tex]F_x = 34.64 \ N[/tex]
So
[tex]W = 34.64 * 7[/tex]
=> [tex]W = 242.5 \ J[/tex]
Considering question b
From the question we are told that
The mass of the toy baby stroller is [tex]m = 20 \ kg[/tex]
The distance covered is [tex]d = 4 \ m[/tex]
The force the girl applies on the handle is [tex]F = 60 \ N[/tex]
Generally the workdone is mathematically represented as
[tex]W = F * d[/tex]
=> [tex]W = 60 * 4[/tex]
=> [tex]W = 240 \ J[/tex]
Select all the correct answers.
Which statements are true?
A farsighted person's cornea and lens refract light too much.
A nearsighted person's cornea and lens do not refract light enough.
A person whose eyes are blue has irises that reflect blue light.
Even people with perfectly working eyes have a blind spot in each eye.
A lens with cataracts absorbs or scatters light that it should refract.
Answer:
e
Explanation:
Answer: E B
Explanation:
Which of the following examples best represents an object with balanced forces acting upon it?
A - A boat accelerating through the water.
B - A book sitting at rest on a high shelf.
C- A wagon rolling down a steep hill.
D- A baseball thrown into the air.
Answer:the answer is “A book sitting on a high shelf” :)
Explanation:
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 solid disk rotates in the horizontal plane at an angular velocity of 0.649 rpm with respect to an axis perpendicular to the disk at its center. The moment of inertia of the disk is 0.101 kg m2. From above, sand is dropped straight down onto this rotating disk, so that a thin uniform ring of sand is formed at a distance of 0.415 m from the axis. The sand in the ring has a mass of 0.499 kg. After all the sand is in place, what is the angular velocity of the disk
Answer:
The angular velocity of the disk is 0.0369 rad/sec.
Explanation:
Convert 0.649 rpm to rad/s
0.649 rpm = 0.649 * (2π/60) = 0.0679rad/sec
From the question,
Summation of final angular momentum equals summation of initial angular momentum
I*w = Io*wo
w = wo (lo/I)
But I = Isand + Io
and Isand = Msand * R²sand
Therefore, w = wo (lo/I) = wo (Io/Msand * R²sand + Io)
Where,
wo = 0.0679rad/sec
Io = 0.101 kg m2
Msand = 0.499 kg
Rsand = 0.415 m
Hence,
w = 0.0679 {0.101/(0.499*(0.415)²+0.101)}
w = 0.0679 (0.101/0.1869)
w = 0.0679*0.544 = 0.0369 rad/sec
The angular velocity of the disk is 0.0369 rad/sec.
The rate of change of velocity or speed is known as acceleration. If a car increases it speed form 10 to 20m/s in 2 seconds, then what is its rate of change in velocity?
A) 5 m/s/s
B) 10 m/s/s
C) 20 m/s/s
D) 40 m/s/s
Answer:
A) 5 m/s/s
Explanation:
Given the following data;
Initial velocity = 10m/s²
Final velocity = 20m/s²
Time, t = 2 seconds.
In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.
Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.
Mathematically, acceleration is given by the equation;
[tex]Acceleration, a = \frac{final \; velocity - initial \; velocity}{time}[/tex]
Substituting into the equation, we have;
[tex]Acceleration, a = \frac{20 - 10}{2}[/tex]
[tex]Acceleration, a = \frac{10}{2}[/tex]
Acceleration, a = 5m/s²