Find the direction and magnitude of :
1. The vector sum A + B [10. 22m, 145. 16°]
2. The vector A - B, [49. 56m, 157°] and
3. The vector difference B - A. [49. 56m, 337].
​

Answer:

1,000,000,000,000,000,000 km (about 100,000 light years or about 30 kpc)

Explanation:

If the forest ecosystem experienced an extreme drought that cut the population of primary producers in half, it would have a significant impact on the food chain and the overall health of the ecosystem.

Primary producers, such as plants and trees, are the foundation of the food chain, and without them, the entire ecosystem would suffer.

The animals that rely on these primary producers for food would also experience a decline in population, which could ultimately lead to a collapse of the food chain.

Additionally, the reduction in primary producers could lead to increased soil erosion, as the roots of the plants help to stabilize the soil. The loss of vegetation could also lead to an increase in carbon dioxide levels, as there would be fewer plants to absorb it through photosynthesis.

Overall, an extreme drought that cut the population of primary producers in half would have far-reaching consequences for the forest ecosystem, and it would take many years for the ecosystem to recover.

To learn more about ecosystem, refer below:

https://brainly.com/question/13979184

#SPJ11

The investigation provides a useful method for determining the composition of a wedding ring, but caution should be taken in interpreting the results due to potential sources of error.

a) To investigate whether the wedding ring is made of pure gold or a mixture of gold and silver, we can use the density of the ring as a clue. Firstly, we need to weigh the ring using a scale with high precision. Then, we can calculate the volume of the ring by measuring its dimensions and using the formula for the volume of a cylinder (V=πr²h). Once we have the weight and volume of the ring, we can calculate its density by dividing the weight by the volume. If the density of the ring is close to the density of pure gold (19.3g/cm³), then the ring is likely to be made of pure gold. However, if the density of the ring is lower than that of pure gold, it may indicate that the ring is made of a mixture of gold and silver.

b) The most significant source of error in our investigation is that the ring may contain other metals or impurities that affect its density. Additionally, the precision of the scale and measurements of the ring's dimensions can also affect the accuracy of our calculations. Therefore, we need to use high-precision instruments and repeat our measurements several times to ensure the accuracy of our results.

Know more about Density here:

https://brainly.com/question/28557244

#SPJ11

Answer:

b. As distance increases, magnetic force decreases.

Explanation:

The correct answer is b. As distance increases, the magnetic force decreases. Magnetic force obeys an inverse square law with distance. This means that the force is inversely proportional to the distance squared. For example, if the distance between two magnets is doubled, the magnetic force between them will fall to a quarter of the initial value.

Based on information the statement that is true is A. The sun's gravity makes the planets orbit around it.

Gravity is a fundamental force of nature that exists between all objects with mass or energy. The force of gravity depends on the mass of the objects and the distance between them. In the case of the solar system, the sun's gravity is the dominant force that controls the motion of the planets.

The planets are constantly pulled towards the sun by its gravitational force, causing them to orbit around it in elliptical paths. This is known as Kepler's laws of planetary motion.

Learn more about Gravity at:

https://brainly.com/question/557206

#SPJ1

Answer:

My most interesting branch of science is psychology the study of the human mind branches out into so many different fields and effects everything even how we science

Explanation:

A) Johann Winckelmann assisted Anton Raphael Mengs with the iconography of his ceiling fresco, Parnasus, in the Villa Albani.

The person who assisted Anton Raphael Mengs with the iconography of his ceiling fresco, Parnassus, in the Villa Albani was Johann Joachim Winckelmann. Winckelmann was a German art historian and archaeologist who was highly influential in the development of neoclassicism. He was a friend and collaborator of Mengs, and he provided guidance on the classical iconography and symbolism used in the Parnassus fresco.

The fresco depicts the classical god Apollo surrounded by the Muses, who are engaged in various artistic pursuits, such as poetry, music, and dance. Winckelmann's knowledge of classical art and literature was instrumental in shaping the iconography of the fresco, which remains one of the most important examples of neoclassical art.

Learn more about Raphael  at:

https://brainly.com/question/3038806

#SPJ1

Answer:

given m = 50 kg u = 0 m/s v = 4m/s force = P theta = 30 deg

Explanation:

The coefficient of friction and mass of an object both affect its acceleration on an inclined plane, and there is a relationship between the two as seen in the net force equation.

The coefficient of friction is a measure of the amount of friction between two surfaces in contact. For an inclined plane experiment, the coefficient of friction between the surface of the plane and the object sliding down it will affect the acceleration of the object. Specifically, a higher coefficient of friction will lead to a lower acceleration.

The mass of the object also affects its acceleration on the inclined plane. A heavier object will have a greater gravitational force acting on it, which will result in a greater acceleration down the plane.

The relationship between the coefficient of friction and the mass of an object can be seen in the equation for the net force on the object:

[tex]Fnet = mgsin(\theta) - \mu\;mgcos(\theta),[/tex]

where μ is the coefficient of friction, m is the mass of the object, g is the acceleration due to gravity, and θ is the angle of the inclined plane.

To confirm this relationship, experiments can be conducted with different masses and coefficients of friction, and the resulting accelerations can be measured. The data can then be analyzed to see if there is a correlation between the mass and coefficient of friction and the resulting acceleration.

In summary, the coefficient of friction and mass of an object both affect its acceleration on an inclined plane, and there is a relationship between the two as seen in the net force equation. Experiments can be conducted to confirm this relationship.

To know more about mass refer here:

https://brainly.com/question/18064917#

#SPJ11

Moving a magnet straight through the center of a wire coil is a common way to induce an electric current in the coil. Option A is correct.

Moving a bar magnet straight through the center of a wire coil will cause an electric current to flow in the coil. This is due to Faraday's law of electromagnetic induction, which states that a change in magnetic field induces an electromotive force (EMF) in a closed circuit. When the magnet moves through the wire coil, it creates a changing magnetic field, which in turn induces a current in the wire.

This effect can be used to generate electricity in power plants by rotating a magnet inside a wire coil, which induces a current that can be used to power homes and businesses. It is also the principle behind electric generators and electric motors, which use electromagnetic induction to convert mechanical energy into electrical energy or vice versa. Option A is correct.

To know more about the Magnet, here

https://brainly.com/question/19572276

#SPJ4

Answer:

The basics of proton-proton fusion in the Sun are detailed in the following important summary:

Normally, protons repel each other because their charges are similar. This is similar to trying to bring together the north pole of a magnet with the north pole of another magnet.

To overcome that electromagnetic repulsion, one needs to smash the protons at a very high speed. This is similar to how two magnets can be brought together if they are moving very fast.

That high speed is not achieved in daily life, thankfully, but in the cores of stars where the temperature is high.

Temperature is a proxy for the speed of particles. For example, if it is cold in a room, the particles are moving slowly.

The temperature is high in the cores of stars because there is the sizable mass of all the overlaying layers exerting a pressure on the core. This pressure causes the temperature to rise, and hence the speed of the protons.

By analogy, consider when diving from the top of the pool to the bottom of the pool. As you descend, you begin to feel the pressure exerted by all the overlaying layers of water.

In the core of the Sun, the temperature is about 15 million degrees Celsius. This is hot enough for the protons to move at very high speeds. When two protons collide at high speed, they can fuse together to form a helium nucleus. This process releases a large amount of energy, which is what powers the Sun.

The proton-proton fusion reaction is a complex process, but it is essential for the Sun to shine. Without this reaction, the Sun would eventually cool and collapse.

Shutting down a nuclear reactor can take anywhere from a few minutes to several hours, depending on the type of reactor and the circumstances surrounding the shutdown.

In a normal shutdown, it typically takes a few hours to fully cool down the reactor and bring it to a safe, stable state.

However, in an emergency situation such as a reactor malfunction or natural disaster, the shutdown process may need to be accelerated to prevent a catastrophic event.

In such cases, emergency cooling systems and other safety measures may be employed to shut down the reactor as quickly as possible.

To learn more about malfunction, refer below:

https://brainly.com/question/8884318

#SPJ11

The factors that affect the thermal conductivity of earth materials include porosity, density, mineral composition, moisture content, etc.

The thermal conductivity of earth materials depends on several factors, including:

More on thermal conductivity can be found here: https://brainly.com/question/7643131

#SPJ1

The index of refraction of this medium is 1.36. The index of refraction (n) of a medium is the ratio of the speed of light in vacuum (c) to the speed of light in the medium (v): n = c/v

Given the speed of light in the medium as 2.2 × 10^8 m/s, we can calculate the index of refraction as: n = c/v = (3.0 × 10^8 m/s) / (2.2 × 10^8 m/s) = 1.36

Therefore, the index of refraction of this medium is 1.36. This indicates that light travels slower in this medium compared to a vacuum and is bent when it enters the medium at an angle, a phenomenon called refraction.

To know more about index of refraction, refer here:

https://brainly.com/question/31106652#

#SPJ11

The increase in height of the pendulum is: approximately 2.04 cm, and the velocity of the bob as it passes through the bottom of the swing is approximately 0.894 m/s.

a) To calculate the increase in height, we can use the formula for GPE: GPE = mgh, where m is the mass (50g or 0.05kg), g is the gravitational acceleration (approximately 9.81 m/s^2), and h is the height.

Given that the GPE is 0.1 J, we can rearrange the formula to solve for h:

h = GPE / (mg).

Plugging in the values, we get h = 0.1 / (0.05 * 9.81) ≈ 0.0204 m or 2.04 cm.

b) As the pendulum swings, its GPE is converted to KE at the bottom of the swing. We can use the conservation of energy principle, which states that the total energy (GPE + KE) remains constant. Since the GPE at the top of the swing equals the KE at the bottom,

we can use the formula for KE to find the velocity of the bob:

KE = 0.5 * m * v^2, where m is the mass (0.05kg) and v is the velocity.

We know that the GPE is 0.1 J, so we can set this equal to the KE and solve for v: 0.1 = 0.5 * 0.05 * v^2. Rearranging and solving for v, we get v ≈ 0.894 m/s.

In summary, the increase in height of the pendulum is approximately 2.04 cm, and the velocity of the bob as it passes through the bottom of the swing is approximately 0.894 m/s.

To know more about pendulum, refer here:

https://brainly.com/question/29702798#

#SPJ11

complete question:

Describe the energy changes as a pendulum swings if the pendulum has a mass of 50g and is lifted so that has a GPE of 0. 1 calculate

a. its increase in height

b. the velocity of the bob as it pass through the bottom of the swing

a) The new surface area of one face will be 225.162 cm^2.

b) The volume of the iron cube at the final temperature of 80°C will be  3382.29 cm^3.

The thermal expansion of a solid material can be determined using the coefficient of linear expansion, which is a material property that relates the change in length to the change in temperature. For iron, the coefficient of linear expansion is approximately 1.2 x 10^-5 /°C.

a) To find the new surface area of a face when the temperature rises from 20°C to 80°C, we can use the formula:

ΔA = A_0 * α * ΔT

where ΔA is the change in surface area, A_0 is the initial surface area, α is the coefficient of linear expansion, and ΔT is the change in temperature.

For a cube with each side 15 cm long, the initial surface area of one face is 15 cm x 15 cm = 225 cm^2. The change in temperature is 80°C - 20°C = 60°C. Substituting these values and the coefficient of linear expansion for iron, we get:

ΔA = 225 cm^2 * 1.2 x 10^-5 /°C * 60°C = 0.162 cm^2

Therefore, the new surface area of one face will be 225 cm^2 + 0.162 cm^2 = 225.162 cm^2.

b) To find the volume of the iron cube at the final temperature of 80°C, we can use the formula:

ΔV = V₁ * β * ΔT

where ΔV is the change in volume, V₁ is the initial volume, β is the coefficient of volume expansion, and ΔT is the change in temperature.

For a cube with each side 15 cm long, the initial volume is 15 cm x 15 cm x 15 cm = 3375 cm^3. The coefficient of volume expansion for iron is approximately three times the coefficient of linear expansion, so we can use β = 3α.

Substituting these values and the change in temperature, we get:

ΔV = 3375 cm^3 * 3 * 1.2 x 10^-5 /°C * 60°C = 7.29 cm^3

Therefore, the volume of the iron cube at the final temperature of 80°C will be 3375 cm^3 + 7.29 cm^3 = 3382.29 cm^3.

To learn more about temperature click on,

https://brainly.com/question/12789820

#SPJ4

For an ideal gas, Cp = Cv + Nk starting with H = U + PV and using the fact that H and U are independent of pressure and volume.

Starting with H = U + PV, we can take the partial derivative of both sides with respect to temperature (keeping pressure constant) to get:

dH/dT = dU/dT + P(dV/dT)

But for an ideal gas, we know that P(dV/dT) = Nk, where N is the number of molecules and k is Boltzmann's constant. This is because an ideal gas follows the ideal gas law PV = NkT, which can be rearranged to P = Nk/V and then differentiated with respect to temperature to get P(dV/dT) = Nk.

So substituting this in, we get:

dH/dT = dU/dT + Nk

Now, we also know that for an ideal gas, U only depends on temperature (not pressure or volume), so dU/dT = (dU/dT)v. Similarly, H only depends on temperature and pressure (not volume), so dH/dT = (dH/dT)p.

Therefore, we can rewrite the equation as:

(dH/dT)p = (dU/dT)v + Nk

And using the definition of heat capacity at constant pressure (Cp) and constant volume (Cv), we have:

Cp = (dH/dT)p      and       Cv = (dU/dT)v

So we can write:

Cp = Cv + Nk

Learn more about ideal gas here:-

https://brainly.com/question/28257995

#SPJ11

When energy leaves the sun's core, it travels through the radiative zone in the form of c. electromagnetic waves.

This is also called as radiative energy. The radiative zone is the second zone of the sun, and it is the region where the energy created by nuclear reactions in the core is transferred through the Sun's outer layers. In this zone, the energy moves in the form of photons, which are particles of light that carry the energy.

The radiative zone is characterized by the high temperature and density of its materials, which cause the photons to scatter frequently before they can escape the zone. The photons that make it through the radiative zone eventually reach the convective zone, where they transfer their energy to the gas particles that rise and fall in the Sun's atmosphere through convection currents. These currents help distribute the energy from the core to the outer layers of the Sun and eventually to space.

In summary, the correct answer to the question is c. electromagnetic waves, which travel through the radiative zone as particles of light or photons.

Learn more about electromagnetic waves at: https://brainly.com/question/11820725

#SPJ11

Techniques that are often combined to create more detailed and accurate maps of the universe. The resulting maps provide valuable insights into the evolution, structure, and properties of the universe.

Astronomers create three-dimensional maps of the universe using various techniques, including:

1. Redshift surveys: Astronomers measure the redshift of galaxies to determine their distance and velocity. The redshift is caused by the expansion of the universe, which stretches the wavelength of light from distant objects. By measuring the redshift of many galaxies, astronomers can create a three-dimensional map of the large-scale structure of the universe.

2. Cosmic microwave background radiation (CMB) surveys: The CMB is the oldest light in the universe, and it provides a snapshot of the early universe when it was only 380,000 years old. Astronomers use specialized telescopes to measure the temperature and polarization of the CMB to study the structure and history of the universe.

3. Gravitational lensing: Massive objects like galaxies and clusters of galaxies can bend and distort the light from more distant objects behind them, creating a magnifying effect. By studying the distortions in the light, astronomers can map the distribution of dark matter, which is invisible but exerts a gravitational force.

4. Galaxy surveys: Astronomers can also create three-dimensional maps of the universe by cataloging the positions and properties of large numbers of galaxies. By studying the distribution of galaxies, astronomers can infer the large-scale structure of the universe and the distribution of dark matter.

To know more about Redshift surveys refer here

https://brainly.com/question/24078282#

#SPJ11

Answer:

Option A

Explanation:

If the graph plotted against Distance and Time and the graph is a linear straight line then the body is IN CONSTANT VELOCITY.And Acceleration is 0

The emf induced in the coil is 2.0 volts.

To calculate the emf induced in the coil with 20 turns of wire, wrapped around a tube with a cross-sectional area of 1.0 m², and a magnetic field applied at a right angle at 0.50 T, when it is pulled out of the magnetic field in 5 seconds, we can use Faraday's Law of Electromagnetic Induction.

The formula for Faraday's Law is:

emf = -N * (ΔΦ/Δt)

where

emf is the induced electromotive force,

N is the number of turns in the coil (20),

ΔΦ is the change in magnetic flux, and

Δt is the time it takes to change the flux (5 seconds).

First, we need to calculate the change in magnetic flux (ΔΦ). Since the coil is completely pulled out of the magnetic field, the final magnetic flux will be zero.

The initial magnetic flux (Φ_initial) can be calculated using the formula:

Φ_initial = B * A

where

B is the magnetic field strength (0.50 T) and

A is the cross-sectional area of the tube (1.0 m²).

Φ_initial = 0.50 T * 1.0 m²

              = 0.50 Wb (Weber)

Now, we can calculate the change in magnetic flux (ΔΦ):

ΔΦ = Φ_final - Φ_initial

      = 0 Wb - 0.50 Wb

      = -0.50 Wb

Next, we can plug the values into Faraday's Law formula:

emf = -20 * (-0.50 Wb / 5 s)

       = 20 * (0.10 V)

       = 2.0 V

So, the emf induced in the coil is 2.0 volts.

To know more about emf induced  refer here

https://brainly.com/question/16764848#

#SPJ11

Then  it takes 0.375 seconds for the bullet to reach the target.

To determine the time required for the bullet to reach the target, we can use the formula t = d/v, where t is time, d is distance, and v is velocity. In this case, the distance is 300 meters and the velocity is 800 m/s.

Substituting these values into the formula, we get:

t = 300/800
t = 0.375 seconds


It is important to note that this calculation assumes that there is no air resistance acting on the bullet. In reality, air resistance would cause the bullet to slow down over time, so the actual time required for the bullet to reach the target may be slightly longer than calculated.

Additionally, it is crucial to always follow proper firearm safety protocols and regulations when handling firearms.

To learn more about : target

https://brainly.com/question/29852531

#SPJ11

To determine the frictional torque of the engine's bearings by graphing the data, we need to select appropriate variables to plot on each axis that will produce a straight-line graph with a slope related to the frictional torque.

We know that the frictional torque is directly proportional to the frictional force acting on the bearings. Therefore, one of the variables we should plot on the y-axis is the frictional force. The frictional force is usually measured using a load cell or a torque sensor.

On the other hand, the other variable we should plot on the x-axis is the rotational speed of the engine. The rotational speed of the engine can be measured using a tachometer or a frequency counter.

The reason we choose these two variables is that the frictional force acting on the bearings usually increases linearly with the rotational speed of the engine.

Therefore, plotting the frictional force against the rotational speed of the engine should produce a straight-line graph with a slope related to the frictional torque.

Once we have obtained the straight-line graph, we can calculate the frictional torque by finding the slope of the graph.

The slope of the graph represents the change in the frictional force per unit change in the rotational speed of the engine. Therefore, the slope of the graph can be multiplied by the radius of the bearings to obtain the frictional torque.

In conclusion, to determine the frictional torque of the engine's bearings by graphing the data, we should plot the frictional force against the rotational speed of the engine, as this should produce a straight-line graph with a slope related to the frictional torque.

To know more about frictional torque refer here

https://brainly.com/question/30021872#

#SPJ11

The momentum of a 30 kg block with an initial velocity of 50 m/s encountering a constant 8 N friction force and traveling for 15 seconds is 1680 kg m/s.

The initial momentum of the block is given by:

p = mv = (30 kg) x (50 m/s) = 1500 kg m/s

The net force acting on the block is given by the force of friction:

[tex]F_{net} = F_{friction} = 8 N[/tex]

Using Newton's second law, we can find the acceleration of the block:

[tex]F_{net} = ma[/tex]

8 N = (30 kg) a

[tex]a = 8/30 m/s^2[/tex]

Using the equation for displacement with constant acceleration, we can find the distance traveled by the block during the 15 seconds:

[tex]d = vt + 1/2 at^2[/tex]

[tex]d = (50 m/s)(15 s) + 1/2 (8/30 m/s^2)(15 s)^2[/tex]

d = 750 m + 450 m = 1200 m

Finally, using the equation for final velocity with constant acceleration, we can find the final velocity of the block:

[tex]v_{f^2} = v_{i^2} + 2ad[/tex]

[tex]v_{f^2} = (50 m/s)^2 + 2(8/30 m/s^2)(1200 m)[/tex]

[tex]v_{f^2} = 2500 \;m^2/s^2 + 640 \;m^2/s^2 = 3140\; m^2/s^2[/tex]

[tex]v_f[/tex] = 56.0 m/s

Therefore, the momentum of the block after 15 seconds is:

p = mv = (30 kg)(56.0 m/s) = 1680 kg m/s

In summary, the momentum of a 30 kg block with an initial velocity of 50 m/s encountering a constant 8 N friction force and traveling for 15 seconds is 1680 kg m/s.

To know more about velocity refer here:

https://brainly.com/question/19979064#

#SPJ11

The largest angular size of Jupiter as seen from Earth is 0.022 degrees and the smallest angular size is 0.013 degrees.

To calculate the angular size of Jupiter as seen from Earth, we can use the formula:
Angular size = [tex](\frac{diameter of object}{distance to object})[/tex]×(180° / π)

For the smallest separation between Earth and Jupiter (588 million km), the angular size of Jupiter would be:
Angular size =[tex](\frac{140,000 km}{588 million km})[/tex]×(180° / π) = 0.022 degrees or approximately 1.3 arcminutes

For the largest separation between Earth and Jupiter (968 million km), the angular size of Jupiter would be:
Angular size = [tex](\frac{140,000 km}{968 million km})[/tex]×(180° / π)= 0.013 degrees or approximately 0.8 arcminutes.

To know more about the conversion of angular size into arcminutes visit:

https://brainly.com/question/17311200

#SPJ11

This is because your basal metabolic rate, or BMR, decreases as you age.

Your body burns calories at rest to maintain essential bodily processes like breathing, circulation and cell growth and repair which is referred to as BMR.

Age-related changes in body composition including an increase in body fat and a loss of muscular mass can result in a reduction in BMR.

Therefore, To maintain a healthy weight and overall health as you age, it is crucial to pay attention to your food and physical activity levels. Maintaining a healthy BMR and avoiding weight gain can be achieved by eating a well-balanced diet with sensible portion sizes and exercising frequently.

Learn more about BMR here : brainly.com/question/14095049

#SPJ1

The best way to find experimental evidence of the different types of materials that condensed as a function of distance from the sun during the period of accretion in the solar nebula is through astronomical observations.

By observing the composition of planets and asteroids at different distances from the sun, scientists can determine the types of materials that condensed as a function of distance. For example, the inner planets are composed of denser materials than the outer planets, indicating that different materials condensed at different distances from the sun.

Additionally, by studying meteorites and comets, which are believed to be left over from the formation of the solar system, scientists can gain insight into the composition of materials that condensed at various distances from the sun. Finally, using spectroscopy to analyze the composition of dust in interstellar clouds can provide evidence of the types of materials that condensed at different distances from the sun in the solar nebula.

Know more about solar system here

https://brainly.com/question/12075871#

#SPJ11

Two 100 kg point masses would need to be separated by a distance of 1.4 meters in order to experience a force of 1N between them.

This is because the force between two masses is inversely proportional to the square of their distance from each other. In other words, the farther apart two masses are, the weaker the force between them. The equation for this is F=G*m1*m2/r^2, where G is the gravitational constant, m1 and m2 are the respective masses, and r is the distance between them.

When m1 and m2 are 100 kg and F is 1N, it can be solved to find r = 1.4 meters.

Know more about gravitational  here

https://brainly.com/question/3009841#

#SPJ11

The frequency of the girl's bell heard by her dad is approximately 772 Hz.

1. This problem involves the Doppler effect, which describes how the frequency of a sound wave changes when the source of the sound is moving relative to an observer.

When the source is moving towards the observer, the frequency appears higher, and when the source is moving away from the observer, the frequency appears lower.

We can use the following equation to calculate the frequency of the sound wave heard by the dad:

f' = f(v + vd) / (v - vs)

where f is the frequency of the sound wave emitted by the girl, v is the speed of sound in air, vd is the speed of the dad's car (33.4 m/s), and vs is the speed of the girl on her bicycle (8.54 m/s). f' is the frequency heard by the dad.

Substituting the given values, we get:

f' = f(v + vd) / (v - vs)

f' = 714 Hz * (343 m/s + 33.4 m/s) / (343 m/s - 8.54 m/s)

f' = 772 Hz

To know more about Doppler effect refer here

https://brainly.com/question/15318474#

#SPJ11

The force responsible for normal expiration is supplied by the elastic recoil of the lungs and chest wall. During inhalation, the diaphragm and intercostal muscles contract, causing the chest cavity to expand and the lungs to fill with air.

When the muscles relax, the chest cavity and lungs recoil back to their resting positions, expelling air out of the lungs. The elastic recoil of the lungs and chest wall generates the force needed for normal expiration.

To know more about elastic recoil refer here

https://brainly.com/question/9491266#

#SPJ11