Question 1
2 pts
A 93 kg person is skiing down a snowy hill, traveling at 9 m/s when they hit a 50 kg hiker on the skiing trail, who was standing still. The hiker ends
up moving backwards (in the direction the skier was moving) at 2 m/s after the collision. How fast, in m/s, will the skier be going right after the
collision? Enter your answer as just a number without units.

Suppose that Reid weighs 72 kg. 2. The mouse macaque of India is the shortest primate on Earth, with an average weight of just 30.0 g. Imagine that this lemur swings 

What does the statistical term "average" mean?

Average. In everyday speech, a average is a specific number chosen to represent a collection of figures. In various settings, various average ideas are utilized. The word "average" frequently refers to the mathematical mean, which is the total of the values divided by the number of numbers being averaged. Statistical terms: mean, median

What are the several definitions of average?

In various settings, various average ideas are utilized. The word "average" frequently refers to the mathematical mean, which is the total of the integers divided by the amount of numbers being averaged. Mean, average, and mode all are considered measures of normal distribution in statistics, and in common parlance, any of these could be referred to as an average figure.

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The current flowing through each wire is the experiment's independent variable because it is the one that the experimenter is actively manipulating and controlling.

The resistance is influenced by the wire's thickness, so the thicker the wire, the lower the resistance. Because less water can flow through a narrower pipe in a given length, there is more resistance in a narrower pipe.

Due to the alloy composition of nichrome wire, its resistance is quite high. Because of this, it generates a lot of heat when current flows through it, making it extremely hot to the touch.

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A roller-coaster car is towed up an incline at a steady speed of 0.500 m/s by a chain parallel to the surface of the incline. the slope is 3.00%. ignoring friction, the magnitude of the force exerted on the car by the chain is: 5908.7 N

The magnitude of the force exerted on the roller-coaster car by the chain is equal to the net force on the car, which is equal to the sum of the force due to gravity and the force due to the incline. Since the roller-coaster car is moving at a steady speed, the net force on the car must be equal to zero.

Using Newton's second law of motion, we can calculate the force due to gravity (Fg) and the force due to the incline (Fi) in order to determine the magnitude of the force exerted on the car by the chain.

The force due to gravity (Fg) can be calculated as Fg = m * g, where m is the mass of the roller-coaster car and g is the acceleration due to gravity. Therefore, Fg = 604 kg * 9.8 m/s2 = 5902.8 N.

The force due to the incline (Fi) can be calculated as Fi = m * g * sinθ, where m is the mass of the roller-coaster car, g is the acceleration due to gravity, and θ is the angle of the incline. The angle of the incline is equal to the slope of the incline divided by 100. Therefore, θ = 3.00% / 100 = 0.03 radians.

Therefore, [tex]Fi = 604 kg * 9.8 m/s2 * sin(0.03) = 5.9 N.[/tex]

Therefore, the magnitude of the force exerted on the car by the chain is equal to the sum of the force due to gravity and the force due to the incline. [tex]F = Fg + Fi = 5902.8 N + 5.9 N = 5908.7 N.[/tex]

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1) The heat is 10,800 J

2) The heat is 2400 J

3) The time is 100 s

The heating effect of current, also known as Joule heating or resistive heating, is a phenomenon where electrical energy is converted into heat when an electric current flows through a material that has resistance.

1) We know that;

H = I^2rt

H = (3)^2 * 4 * 5 * 60

H = 10,800 J

2) H = (V^2/R)t

H = (10)^2/5 * 2 * 60

H = 2400 J

3) H =(V^2/R)t

t = H/(V^2/R)

t = H * R/V^2

t = 4 * 10^3 * 10/20^2

t = 100 s

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The pneumatic system is connected to a gripper or clamp that is holding the box of chalk or book, then the plunger's action would cause the gripper or clamp to release the object, allowing it to move.

When you press the plunger on a pneumatic system, such as a pneumatic cylinder, air is forced into the cylinder, causing the piston inside to move outward. If you are using the pneumatic system to move a box of chalk or a book, the outward movement of the piston would cause the attached object to move in the same direction.

However, the movement of the object would also depend on the design and placement of the pneumatic system. For example, if the pneumatic system is connected to a gripper or clamp that is holding the box of chalk or book, then the plunger's action would cause the gripper or clamp to release the object, allowing it to move.

It's also worth noting that the amount of force exerted by the pneumatic system would depend on the pressure and flow of the compressed air, as well as the size and design of the cylinder and piston.

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I don't know sorry didn't make me want you say you didn't know how I feel about me being that way and that I didn't even want you say I was wrong and you didn't want me to be to have a good time

In the movie Interstellar, space exploration plays a crucial role in humanity's survival. Earth is on the brink of environmental collapse, and the protagonist, Cooper, must embark on a space mission to find a new habitable planet for humanity.

For the people in the movie, space exploration is not only essential but also the only hope for the survival of the human race.

In today's society, space exploration is also crucial for several reasons. First and foremost, space exploration provides us with a deeper understanding of the universe and our place in it. It allows us to explore the unknown and discover new things, which can lead to breakthroughs in science and technology. Space exploration has already led to countless technological advancements, such as GPS, solar panels, and medical equipment.

Moreover, space exploration has practical applications in areas such as climate change, national security, and disaster response. For instance, satellite imagery can help track natural disasters and aid in disaster response efforts. Satellites can also help us monitor and understand climate change by gathering data on temperature, weather patterns, and greenhouse gas emissions.

Lastly, space exploration inspires and motivates people, especially young people, to pursue careers in science, technology, engineering, and mathematics (STEM) fields. It can also foster international cooperation and collaboration, as countries work together on space missions.

Space exploration is important for both the people in the movie Interstellar and today's society. It can provide us with a deeper understanding of the universe, lead to technological advancements, and have practical applications in areas such as climate change and disaster response. It can also inspire and motivate people to pursue careers in STEM fields and foster international cooperation. Therefore, investing in space exploration is crucial for the betterment of humanity.

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The speed of a harmonic wave traveling in a medium is given by the product of its wavelength and frequency, i.e.,

v = λ f, where v is the velocity of the wave, λ is the wavelength, and f is the frequency. In this case, the given amplitude of the wave is not needed to calculate the speed. We can simply use the wavelength and frequency provided to find the velocity. Substituting the given values, we get: v = (1.09 m) × (649 Hz) = 706.41 m/s. Therefore, the speed with which the wave travels is 706.41 m/s. Note that the unit of velocity in SI is meters per second (m/s).

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Answer:

Answer:please mark as brainliest

To find the minimum initial speed of the dart so that the combination makes a complete circular loop after the collision, we can use the conservation of energy principle.

First, let's find the total mass of the system after the collision, which is the sum of the masses of the lead sphere and the steel dart:
m = 25.00 kg + 7.00 kg = 32.00 kg

Next, we need to find the height that the system needs to reach in order to make a complete circular loop. This height is equal to the length of the wire:
h = 3.50 m

Now, we can use the conservation of energy principle to find the minimum initial speed of the dart.

The initial kinetic energy of the system is equal to the final potential energy of the system at the top of the loop:
0.5 * m * v^2 = m * g * h

Solving for v, we get:
v = sqrt(2 * g * h)

Plugging in the values for m, g, and h, we get:
v = sqrt(2 * 9.81 m/s^2 * 3.50 m) = 8.30 m/s

Therefore, the minimum initial speed of the dart so that the combination makes a complete circular loop after the collision is 8.30 m/s.

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The doctor asks Annie if she has had any trouble with her eyes, like drooping.

In the given text, Dr. Jones asks Annie if she has had any trouble with her eyes, specifically if they have been drooping. This question suggests that the doctor is trying to assess if Annie has been experiencing symptoms of ptosis, which is a medical condition where the upper eyelid droops due to a weakness or paralysis of the muscles responsible for lifting the eyelid.

Ptosis can be a sign of several neurological conditions and can cause visual impairment or other complications. Therefore, the doctor's question indicates that he is trying to gather more information about Annie's symptoms to make a proper diagnosis and provide appropriate treatment.

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The question is incomplete, the complete question is:

Dr. Jones looked pensive and asked, “Have you had any trouble with your eyes? Like have they been drooping?”

Annie looked confused. “I have had a lot of eye strain and double vision recently. It gets blurry when I stare at the computer screen too long; I seem to get a zillion papers every week. I also think the chlorine level in

the pool is too high. Everyone on the team complains about it because, if your goggles come off , your eyes sting like mad.

The doctor smiled, “I swam before those goggles were even invented, so I know what you mean about stinging eyes. But, I think what you’re telling me goes beyond simple fatigue. I’m going to refer you to a neurologist at the hospital.”

Answer:

I = Q / t           definition of electric current

Q = I * t = 40 C/s * .5 s = 20 Coulombs

The force due to the gravitational attraction between the earth and the spacecraft in n if the mass of the spacecraft is 2300 kg is 2,156.4 N

The formula to calculate the gravitational force between two objects is given by:

F = (G * m1 * m2) / r²

where F is the force of gravitational attraction,

G is the gravitational constant (6.67408 × 10⁻¹¹ N·m²/kg²),

m1 and m2 are the masses of the two objects, and

r is the distance between the centers of the two objects.

Using the given values of mass of the spacecraft (m2) as 2300 kg,

the mass of the Earth (m1) as 5.97 × 10²⁴ kg and the distance between them as the sum of the radius of the Earth and the altitude of the spacecraft,

which is approximately 6,378,000 meters + 400,000 meters = 6,778,000 meters,

we can calculate the gravitational force as:

F = (G * m1 * m2) / r²

F = (6.67408 × 10⁻¹¹  N·m²/kg²) * (5.97 × 10^24 kg) * (2300 kg) / (6,778,000 meters)²

F = 2,156.4 N (approx.)

Therefore, the force due to gravitational attraction between the Earth and the spacecraft is approximately 2,156.4 N.

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Answer:

To solve this problem, we need to use the formula:

distance = initial velocity x time + 1/2 x acceleration x time^2

where:

initial velocity = 72 km/hour (we need to convert this to m/s to use it in the formula)

time = 5 seconds

acceleration = 10 m/s^2 (assuming this is the acceleration due to gravity)

Converting the initial velocity from km/hour to m/s:

72 km/hour = (72 x 1000 m) / (60 x 60 s) = 20 m/s

Now we can plug in the values into the formula:

distance = 20 m/s x 5 s + 1/2 x 10 m/s^2 x (5 s)^2

distance = 100 m + 1/2 x 10 m/s^2 x 25 s^2

distance = 100 m + 125 m

distance = 225 meters

Therefore, the distance traveled by the bus in 5 seconds is 225 meters.

The minimum possible diameter of the laser's exit aperture to achieve a 2.0 km diameter spot on the moon is 2.4 meters.

What is the laser pointer? The laser pointer is a compact laser light-emitting device. A laser pointer operates on the principle of stimulated emission. It is possible to get a bright, coherent light beam when photons come together and stimulate one another's emission.

What is a Helium-Neon Laser? The He-Ne laser or Helium-Neon Laser is a gas laser in which a mixture of helium and neon is used as the active medium. This laser is widely used in research laboratories and industries due to its easy availability and low cost. The wavelength of light produced by He-Ne laser is 632.8 nm.

What is a laser beam? A laser beam is a coherent and collimated light beam of photons traveling in the same direction with the same frequency and amplitude. A laser beam emits light rays that can travel great distances with minimal dispersion, as well as exert an incredibly focused level of energy.

When a laser is pointed at the moon from Earth, the beam is so diffuse that the spot on the lunar surface is roughly 610 km in diameter, approximately 20% of the moon's diameter. The laser spot on the moon needs to be no more than 2.0 km in diameter in order to detect the reflected light.

Given that the wavelength of the laser beam is 650 nm. The minimum possible diameter of the laser's exit aperture can be determined using the formula of diffraction-limited beam radius: r = 1.22 * λ * f / D where, λ = 650 nm, the wavelength of the laser f = focal length of the beam D = diameter of the laser's exit aperture

The diameter of the laser's exit aperture is given by the formula: D = 1.22 * λ * f / r.

To achieve a 2.0 km diameter spot on the moon, the minimum possible diameter of the laser's exit aperture is 2.4 meters.

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The glasses that  increase pupil illumination is  Glasses do not increase pupil illumination.​

Pupil illumination refers to the amount of light entering the eye through the pupil. The size of the pupil determines the amount of light that enters the eye, with larger pupils allowing more light and smaller pupils allowing less light. The amount of light available in the environment also affects pupil illumination, with brighter environments causing the pupil to constrict and dimmer environments causing the pupil to dilate. Pupil illumination plays an important role in visual perception, as it affects the brightness and clarity of the visual image formed on the retina.

Pupil illumination is a function of the amount of light entering the eye, which is determined by the size of the pupil and the amount of light available in the environment. Glasses do not have a direct effect on the size of the pupil or the amount of light in the environment, so they cannot increase pupil illumination.

However, glasses can improve visual acuity and clarity by correcting refractive errors and enhancing contrast, which may indirectly improve the perception of brightness and illumination.

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The tension T in the string just after the objects are released must be equal and opposite to the accelerations of each mass.

The statement refers to a physical principle known as Newton's third law of motion, which states that for every action, there is an equal and opposite reaction.

In the context of the given statement, it means that the tension (T) in the string, which is the force transmitted through the string, must be equal in magnitude and opposite in direction to the accelerations of each mass.

When objects are released and allowed to move under the influence of gravity, they may be connected by a string or rope. As the objects accelerate due to the force of gravity, the tension in the string changes to keep the objects connected and moving together.

According to Newton's third law, the tension in the string must be equal and opposite to the accelerations of each mass.

If one of the objects has a greater acceleration, the tension in the string must be higher on that side to counteract the greater acceleration.

Similarly, if one of the objects has a lower acceleration, the tension in the string must be lower on that side. This ensures that the net force on each object is balanced and that they move together without breaking the string.

This is because Newton's Second Law states that the sum of the forces on an object is equal to the mass times the acceleration: F = ma. Therefore, the tension T must be the same for both masses, since their accelerations must be equal and opposite.

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To calculate the magnitude of the linear momentum for each of the cases, you need to use the following equation:

Linear momentum (p) = mass (m) x velocity (v)

Case (a): Linear momentum (p) = 1.67 x 10-27 kg x 5.00 x 106 m/s = 8.35 x 10-22 kg m/s

Case (b): Linear momentum (p) = 0.015 kg x 300 m/s = 4.5 kg m/s

Case (c): Linear momentum (p) = 75.0 kg x 10.0 m/s = 750 kg m/s

Case (d): Linear momentum (p) = 5.98 x 1024 kg x 2.98 x 104 m/s = 1.78 x 1029 kg m/s

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Answer:

Fission occurs when a neutron slams into a larger atom, forcing it to excite and split into two smaller atoms—also known as fission products. Additional neutrons are also released that can initiate a chain reaction. When each atom splits, a tremendous amount of energy is released.

Explanation:

Answer:

Fission

Explanation:

this happens when the neutrons an atoms slams into a larger atom, forcing it to split into two smaller atoms

When a magnetic field is applied perpendicular to the direction of current in a metallic slab, a voltage is produced in the direction perpendicular to both the magnetic field and the current.

This phenomenon is known as the Hall effect, and the voltage produced is called the Hall voltage. The direction of the Hall voltage is determined by the right-hand rule. If you point your thumb in the direction of the current, and your fingers in the direction of the magnetic field, the Hall voltage will be in the direction perpendicular to both (i.e., it will be perpendicular to the plane defined by your thumb and fingers). The Hall effect is commonly used to measure the strength of magnetic fields and the properties of materials. It is also used in electronic devices such as Hall effect sensors and magnetometers.

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Answer: The Earth is an oblate spheroid, meaning it is roughly spherical in shape but flattened at the poles and bulges at the equator. This shape has been scientifically proven through centuries of evidence and observations. While some people may claim that the Earth is flat, this idea is not supported by scientific evidence.

The impulse that acts on the shoe during its collision with the wall is -15 kg*m/s (to the left).

Calculation steps:

The initial momentum of the shoe, p1 = mv1 = 0.3 kg * 20 m/s = 6 kgm/s (to the right)

The final momentum of the shoe, p2 = mv2 = 0.3 kg * (-30 m/s) = -9 kgm/s (to the left)

The change in momentum, Δp = p2 - p1 = -9 kgm/s - 6 kgm/s = -15 kg*m/s (to the left)

Therefore, the impulse acting on the shoe during its collision with the wall is J = Δp = -15 kg*m/s (to the left)

What is impulse?

Impulse refers to the change in momentum of an object when a force is applied to it for a certain amount of time. It is defined as the product of the force and the time for which it acts on an object. Mathematically, impulse can be expressed as:

J = F * Δt

where J is the impulse, F is the force applied, and Δt is the time for which the force acts.

What is momentum?

Momentum is a physical quantity that measures the motion of an object. It is defined as the product of an object's mass and velocity. In other words, momentum = mass x velocity.

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Answer:

To solve this problem, we need to use the coefficient of thermal expansion for gasoline, which tells us how much the volume of gasoline will increase as its temperature increases. The coefficient of thermal expansion for gasoline is approximately 950 x 10^-6 /°C.

Using this information, we can calculate the increase in volume of gasoline as it warms up from 15°C to 35°C:

ΔV = V * α * ΔT

where V is the initial volume of gasoline (60 L), α is the coefficient of thermal expansion for gasoline (950 x 10^-6 /°C), and ΔT is the change in temperature (20°C).

ΔV = 60 * 950 x 10^-6 * 20

ΔV = 0.114 L

Therefore, the amount of gasoline spilled as it warms up from 15°C to 35°C is:

60 L - 0.114 L = 59.886 L

Explanation:

So the answer is (A) 50.2 litre.

The correct option is (b). Photons of blue light have more energy than photons of green light. So, if there is a current in a photoelectric-effect apparatus with green light, then there will also be a current with blue light.

The photoelectric effect is the process where a material emits electrons when light is shone on it. The effect is generally associated with the emission of electrons when a metal surface is illuminated. In other words, the photoelectric effect refers to the emission of electrons from a metal when it is illuminated with light.

The energy of each photon is directly proportional to its frequency. Therefore, the photoelectric effect depends on the frequency of the incident light. If the frequency of the light is high enough, electrons can escape the surface of the metal. However, the number of electrons emitted is proportional to the intensity of the light, not its frequency.

Therefore, in this case, the cathode is illuminated with blue light. As photons of blue light have more energy than photons of green light, there will also be a current with blue light.

Thus, a current will necessarily be detected if the cathode is illuminated with blue light since photons of blue light have more energy than photons of green light.

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Answer:

12.928 kJ

Explanation:

To calculate the energy required to melt a substance, we use the formula:

Q = m * ΔHfus

where Q is the energy required, m is the mass of the substance, and ΔHfus is the heat of fusion, which is the amount of energy required to melt one gram of the substance.

For methane, the heat of fusion is 0.202 kJ/g. We can calculate the amount of energy required to melt 64g of methane as follows:

Q = m * ΔHfus

Q = 64g * 0.202 kJ/g

Q = 12.928 kJ

Therefore, it takes approximately 12.928 kJ of energy to melt 64g of methane at 90K.

The ratio of diameter of lenses to its focal length is referred as the f-number or f-stop

The ratio of diameter of lenses to its focal length is referred to as the f-number or f-stop. It is a fundamental parameter that describes the aperture of a lens, which determines the amount of light that can pass through the lens. The f-number is calculated by dividing the focal length of the lens by the diameter of the aperture, which is the opening that controls the amount of light entering the lens.

A smaller f-number indicates a larger aperture, which allows more light to enter the lens, resulting in a brighter image and a shallower depth of field. Conversely, a larger f-number indicates a smaller aperture, which allows less light to enter the lens, resulting in a darker image and a greater depth of field.

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The position of the image of the object would be 7.5 cm behind the mirror.

The focal lengths of all convex mirrors are negative and are given by the following formula:

1/f = - (1/R)

where:

Substituting for R in the equation, we are going to have:

1/f = -1/20 cm

f = -20 cm

Next, we can make use of the mirror formula to find the position of the image along the plane of the mirror:

The mirror formula goes thus:

1/f = 1/do + 1/di

where 'do' is the object distance and di is the image distance.

Substituting the values of f and di:

1/-20 cm = 1/12 cm + 1/di

Thus:

di = -7.5 cm

That the di is negative is an indication that the image is a virtual one that forms behind the mirror. In other words, the position of the image is 7.5 cm behind the mirror.

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Metamorphosis refers to the process of development and change in the body form of certain animals as they grow from juveniles to adults.

Explain the types of metamorphosis?

Metamorphosis is classified into two types: complete and incomplete.

1. Complete metamorphosis:

Complete metamorphosis is a developmental process in which the juvenile form of an animal goes through four distinct stages: egg, larva, pupa, and adult. In this type of metamorphosis, the juvenile form looks completely different from the adult form in terms of appearance, behavior, and habitat.

Animals that undergo complete metamorphosis include:

a) Butterflies and moths: The egg hatches into a caterpillar (larva) that feeds and grows rapidly. The larva then forms a pupa or chrysalis, where the body undergoes a complete transformation into an adult butterfly or moth.

b) Flies: The egg hatches into a worm-like maggot (larva) that feeds and grows. The maggot then transforms into a pupa, and finally, an adult fly emerges.

c) Beetles: The egg hatches into a grub (larva) that feeds and grows. The grub then transforms into a pupa, and finally, an adult beetle emerges.

Incomplete metamorphosis:

Incomplete metamorphosis is a developmental process in which the juvenile form (nymph) of an animal resembles the adult in appearance and habitat, but is smaller and lacks wings. The nymph goes through several stages of growth and molting before reaching adult form.

Animals that undergo incomplete metamorphosis include:

a) Grasshoppers: The egg hatches into a nymph that resembles the adult grasshopper but lacks wings. The nymph goes through several molts and growth stages before developing wings and reaching the adult stage.

b) Cockroaches: The egg hatches into a nymph that resembles the adult cockroach but lacks wings. The nymph goes through several molts and growth stages before developing wings and reaching the adult stage.

c) Dragonflies: The egg hatches into a nymph that lives in water and resembles the adult dragonfly but lacks wings. The nymph goes through several molts and growth stages before developing wings and emerging from the water as an adult dragonfly.

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The Young's modulus for a 3D crystal can be estimated using the group velocity equation for 1D crystals by making the following assumptions:

The equation for Young's modulus in a 3D crystal is then: E = ρ v2, where ρ is the mass density and v is the group velocity.

The group velocity can be estimated using the group velocity equation for 1D crystals: v = (dω/dK)-1. Here, ω is the angular frequency and K is the wave vector.

By combining these two equations, the Young's modulus for a 3D crystal can be estimated using the group velocity equation for 1D crystals.

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Answer:- When they are placed in series.

When multiple emf sources are connected in series then the net or total emf is equal to the sum of their individual emfs .

Say if we have cells of emfs [tex]\epsilon_1[/tex] , [tex]\epsilon_2[/tex] , [tex]\epsilon_3[/tex] , [tex]\epsilon_4 [/tex] . . . . [tex]\epsilon_n[/tex]

Then the net emf is ,

[tex]\implies \underline{\underline{\green{\epsilon_{net}= \epsilon_1+ \epsilon_2+\dots +\epsilon_n}}}\\[/tex]

Additional information:-

If the emfs of n cells are equal and they are connected in series then the net emf is given by ,

[tex]\implies \epsilon_{net}= n\epsilon \\[/tex]

where ,

Also , when n cells of emfs [tex]\epsilon_1[/tex] and [tex]\epsilon_2[/tex] . . . . . [tex]\epsilon_n[/tex] and internal resistances [tex]r_1[/tex] , [tex]r_2[/tex] . . . . . [tex]r_n[/tex] respectively are connected in parallel then the net emf is given by,

[tex]\implies \underline{\underline{\green{\epsilon_{net} = \left( \dfrac{1}{r_1}+\dfrac{1}{r_2}+\dots +\dfrac{1}{r_n}\right)^{-1}\left(\dfrac{\epsilon_1}{r_1}+\dfrac{ \epsilon_2}{r_2}+\dots +\dfrac{\epsilon_n}{r_n}\right)}}}\\[/tex]

Again suppose if we make a parallel arrangement of cells each having same emf then the net emf remains same that is equal to the emf of individual cell ( Why ? You can try yourself by using the above formula )

and we are done!