a model rocket is launched with an initial upward velocity of . the rocket's height (in feet) after seconds is given by the following. find all values of for which the rocket's height is feet.

During photosynthesis, light energy is converted into an electron flow in the reaction center chlorophyll.

Photosynthesis can be defined as a biological and chemical process through which green plants (autotrophs) convert light energy (sunlight) into chemical energy.

In Science, photosynthesis is represented by the following chemical reaction:

\(Carbon \;dioxide + water + light energy \rightarrow sugar + oxygen\)

In conclusion, the electrons found within the pigment molecules are excited by visible light, which is then converted into an electron flow in the reaction center chlorophyll.

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Purge units are designed to remove noncondensables from a refrigeration system.To keep refrigeration equipment running at peak performance and to avoid equipment breakdowns and lost product, it is important to maintain and operate the equipment properly.

One crucial maintenance component of a refrigeration system is the purge unit.Purge units are designed to remove noncondensables from a refrigeration system. When air enters a refrigeration system, it becomes trapped and accumulates, reducing the efficiency of the system and increasing the likelihood of breakdowns.

To avoid this, purge units work to remove the air and other noncondensable gases from the system through an air eliminator. The purge unit automatically releases the air and other noncondensable gases as they accumulate, keeping the refrigeration system running smoothly and efficiently.

Aside from purging the refrigeration system of noncondensables, some purge units can also be used to detect leaks in the system. If the purge unit is calibrated properly, it can identify the specific gas that is being released and alert the maintenance team to any potential leaks in the system. In addition, some purge units also have the ability to capture and reuse the refrigerant that is released, making them more environmentally friendly.

In summary, purge units are essential components of refrigeration systems that work to remove noncondensable gases from the system to ensure it runs at peak performance.

These units not only help to keep the system operating smoothly but also have the added benefit of detecting any potential leaks in the system. With regular maintenance and proper operation of the purge unit, refrigeration equipment can provide reliable service and reduce the likelihood of equipment failure and lost product.

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Answer:

They generate electricity by contact.

Explanation:

The observation presented by the question above shows an example of electricity generated by the contact, which can also be called triboelectrification. This type of electricity is created when two objects made of different materials come into contact with each other, and that contact is interrupted soon afterwards, as occurs when someone, wearing woolen socks, walks over the carpet.

For triboelectrification to occur, it is necessary that at least one of the objects involved is electrically charged. This object, when in contact with another object, will transfer electrons carrying the neutral object, until the two objects have the same electrical potential. When interrupting the contact between the objects, the two are left with equal loads of energy.

We have that the magnitude of the magnetic field is determined by the amount of current produced.

Generally,  the magnetic field strength is called the tesla This  is measured as one Newton per ampere-meter.

Electromagnet is a  magnet where the magnetic field is created by an electric current,

Therefore the magnitude of the magnetic field is determined by the amount of current produced

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The final answer are average electric field in the fringe region is smaller than in the central region in parallel electrodes.

According to Gauss's law, the electric field's magnitude E between two parallel plates carrying uniform charge densities σ1 and σ2 in a vacuum is given by the formula; E = σ1 - σ2 / ε0 where ε0 is the permittivity of free space.

A fringe region is formed near the edges of parallel plates, where the electric field's strength is weak due to the presence of fringe fields.

The electric field between two plates with uniform charge densities is constant over the central region and weaker at the edge region.

So, the average electric field in the fringe region is smaller than in the central region.

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The wavelength of the incident light is approximately 314 nanometers.

The energy of a photon of light is given by:

E = hc/λ

where E is the energy of the photon, h is Planck's constant, c is the speed of light, and λ is the wavelength of the light.

In photoelectric emission, the energy of the incident photon must be greater than or equal to the work function (ϕ) of the metal in order for an electron to be ejected. The energy of the ejected electron is given by:

K = E - ϕ

where K is the kinetic energy of the electron.

In the case of the stopping potential (V_stop), the kinetic energy of the ejected electrons is equal to the potential energy required to stop them, so we have:

K = eV_stop

where e is the elementary charge.

Combining these equations, we get:

E = K + ϕ = eV_stop + ϕ

Substituting the values given in the problem, we get:

hc/λ = eV_stop + ϕ

(6.626 ×  J s) × (3.00 × \(10^8\) m/s) / λ = (1.602 × 10⁻¹⁹ C) × (7.5 V) + (3.1 eV) × (1.602 × 10⁻¹⁹ J/eV)

λ = hc / (eV_stop + ϕ)

λ = (6.626 ×10⁻³⁴ J s) × (3.00 × \(10^8\)m/s) / [(1.602 ×  10⁻¹⁹ C) × (7.5 V) + (3.1 eV) × (1.602 × 10⁻¹⁹J/eV)]

λ = 3.14 ×10⁻⁷ m

So the wavelength of the incident light is approximately 314 nanometers.

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Answer:

melting ice cream

Explanation:

in order for the ice cream to melt, thermal energy (heat) must be applied to it.

Answer:

it's 100m/s2

Explanation:

a=f/m

or,a=5/50/1000. (mass si unit is kg and 1kg=1000g

or,a=5/0.005

or,a=100m/s2

The ostrich's average speed during the 3.0 km run is approximately 38.65 km/h.

The average speed of the ostrich during the entire 3.0 km run, we need to calculate  the total time taken for both segments and then divide the total distance by the total time.

Calculate the time for each segment:

Time taken for the first 1.5 km segment at 58 km/h:

Time = Distance / Speed

= 1.5 km / 58 km/h

≈ 0.02586 hours

Time taken for the second 1.5 km segment at 29 km/h:

Time = Distance / Speed

= 1.5 km / 29 km/h

≈ 0.05172 hours

Calculate the total time:

Total Time = Time for the first segment + Time for the second segment

Total Time ≈ 0.02586 hours + 0.05172 hours

≈ 0.07758 hours

Calculate the average speed:

Average Speed = Total Distance / Total Time

Average Speed = 3.0 km / 0.07758 hours

≈ 38.65 km/h

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Could someone help me? A cannon is fired with an initial horizontal velocity of 20 m/s and initial vertical velocity of 25 m/s . After 3s in the air, the canon hits its target. How far away was the canon from its target?

A high jumper leaves the ground with an initial velocity of 10 m/s rightward at an angle of 15 degrees . What is the high jumper's initial horizontal velocity?

After travelling 2.0 m up the inclined plane, the block's speed is roughly 11.6 m/s.

Assuming that there is no friction, we can use the conservation of energy principle to solve this problem.

The initial kinetic energy of the block is given by:

K₁ = (1/2) * m * v₁²

where m is the mass of the block, v₁ is the initial speed, and K₁ is the initial kinetic energy.

The final kinetic energy of the block after it has traveled a distance of 2.0 m up the incline is given by:

K₂ = (1/2) * m * v₂²

where v₂ is the final speed and K₂ is the final kinetic energy.

The potential energy gained by the block due to its increase in height is given by:

U = m * g * h

where g is the acceleration due to gravity and h is the height gained by the block.

Since energy is conserved, the initial kinetic energy plus the gained potential energy must equal the final kinetic energy:

K₁ + U = K₂

Substituting the expressions for K₁, K₂, and U, we get:

(1/2) * m * v₁² + m * g * h = (1/2) * m * v₂²

Simplifying and solving for v2, we get:

v₂ = √(v₁² + 2gh)

where h is the height gained by the block, which is equal to:

h = d * sin(θ)

where d is the distance traveled along the incline and θ is the angle of the incline.

Substituting the given values, we have:

v₁ = 9.0 m/s

θ = 38°

d = 2.0 m

g = 9.81 m/s²

So, h = 2.0 m * sin(38°) ≈ 1.22 m

Substituting these values into the equation for v₂, we get:

v₂ = √((9.0 m/s)² + 2 * 9.81 m/s² * 1.22 m) ≈ 11.6 m/s

Therefore, the block's speed after it has traveled 2.0 m up the inclined plane is approximately 11.6 m/s.

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The momentum of the van after the collision will be -9600 kg m/s.

Momentum is a concept in physics that is used to describe an object's resistance to changes in motion. It is based on the principle of inertia, which states that an object will remain in a state of rest or constant motion unless acted upon by an outside force. Momentum is calculated by multiplying the mass of an object by its velocity. Momentum is a vector quantity, meaning that it has both magnitude and direction. Momentum is also conserved, meaning that the total momentum of any closed system remains constant.

Momentum is a measure of an object's mass multiplied by its velocity. Before the collision, the momentum of the van was 9600 kg m/s (80kg x 72m/s). After the collision, both vehicles will be travelling in the opposite direction, meaning that the momentum of the van will be the same as before, but in the opposite direction. Therefore, the momentum of the van after the collision will be -9600 kg m/s. The change in momentum, or delta momentum, of the van after the collision is the difference between the before and after momentum, or 9600 kg m/s.

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Answer:

\(\huge\boxed{\sf F= 350 \ N}\)

Explanation:

Considering pivot as the central point,

Key:

\(F_1r_1=F_2r_2\)

Here,

Substitute the givens in the above formula.

\(F(1.2)=600(0.7)\\\\F(1.2)=420\\\\Divide \ 1.2 \ to \ both \ sides\\\\F=420/1.2\\\\F= 350 \ N\\\\\rule[225]{225}{2}\)

Explanation:

show me the paper so that way i can answer your question

Answer: the answer is 4

Explanation:

a) The uniform aluminum beam 9.00 m long, weighing 300 N, rests symmetrically on two supports 5.00 m apart. The boy weighing 600 N starts at point A and walks towards the right.

The beam will experience the weight of the boy in two places: at A and somewhere between A and B, depending on how far the boy walks.The upward forces FA and FB exerted on the beam at points A and B, respectively, as functions of the coordinate x of the boy are given in the following two graphs.b) The total force exerted by the boy when he reaches point B is FB + 600 N. The beam will start to tip if the total force's vertical line passes the left support, which carries 900 N vertically. Thus, we want the left and right vertical forces to be equal to avoid any tipping.900 N = FB + 600 N => FB = 300 N300 N = w = mg => m = 30.6 kg.Since the boy weighs 600 N, the load the beam carries is 900 N plus some variable force F(x). Therefore, to maintain equilibrium, the following force balance equation must be satisfied:F(x) = w + FA = 900 N + 600 N = 1500 NWhere FA is the upward force at A for a boy at position x. Since the beam is uniform, the following moment balance equation must be satisfied:900N/2 * 5m + (5m - x) * FA + (9m - 5m - x) * 1500N = (5m - x) * FB + 900N/2 * 5mSolving the above equation for FA and FB, we getFA = 3000 N - 300 N/x and FB = 900 N + 600 N - 300 N/x.(c) The boy will walk just to the end of the beam without tipping it if the vertical forces on the left and right sides of the beam are balanced. Thus, to maintain equilibrium, we have:FB + w = FA900 N + 600 N = FAFor the beam to remain balanced, FA must act at the beam's right end, as shown in the diagram below:We may now use moments to determine the distance between support B and the beam's right end. For the beam to remain balanced, the sum of moments about support A must be equal to zero:FB * 5m + w * (5m + x) = FA * 9mFB * 5m + 300 N * (5m + x) = 900 N + 600 N (from part b) * 9mFB = 300 N (1 + 2x/9)Thus, the distance between support B and the beam's right end is given by:5m + 9m - x - 5m = 9m - x = (5/3) m = 1.67 m.

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To reduce the resonant frequency of a mass, I would b)increase the mass .So, correct option is b.

A thunderous recurrence is the normal vibrating recurrence of an item and indicated as 'f' with an addendum zero (f 0). At the point when an item is in balance with acting powers and could continue to vibrate for quite a while under wonderful circumstances, this peculiarity is reverberation.

We know very well that resonant frequency of simple harmonic motion system is given by 2π√k/m where k is spring constant and m is the mass of the body,

Now, we can see that frequency is inversely proportional to mass and directly proportional to spring constant.

Now, on increasing the spring constant we can see that resonant frequency will also rise.

On increasing the mass of the body resonant frequency will decrease since resonant frequency is inversly proportional to mass.

Increasing the damping will not effect the resonant frequency since frequency does not depend on the material of the body.

Hence, option b is correct.

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(Complete question) is:

Suppose that you wanted to reduce the resonant frequency of a mass and spring harmonic motion system, what could you do?

a)increase the spring constant

b)increase the mass

c)decrease the spring constant

d)increase the damping.

Answer:343m

Explanation:

B

Explanation:

yeah but I don't know what

Answer:

Explanation:

Distance = speed *time

as per the question, THE average speed is 40Km/h

time1 = S/40,time2 = S/40

now , time1 +time2

s/40+s/40

The time taken for Arun's journey can be calculated by dividing the distance to his school by the average speed. Assuming the school is 20km away, at an average speed of 40km/h, it would take Arun 30 minutes to reach school.

The question involves applying the concept of speed as being the distance traveled divided by the time it takes to get to the destination. To determine how long Arun's journey takes taking into account the average speed of 40km/h, we need to know the distance to school. However, if we assume the distance as 'd' kilometers, the time taken can be found by the formula: time = distance/speed

Let's say, for example, Arun’s school is 20 kilometers away. Using the formula time = distance/speed, we substitute the distance and speed into the formula: time = 20km / 40km/h = 0.5 hours. To convert this time into minutes, we multiply by 60 (since there are 60 minutes in an hour), which gives us 30 minutes. Therefore, if Arun’s school was 20 kilometers away, his journey would take him 30 minutes.

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Answer:

a. The total momentum of the trolleys which are at rest before the separation is zero

b. The total momentum of the trolleys after separation is zero

c. The momentum of the 2 kg trolley after separation is 12 kg·m/s

d. The momentum of the 3 kg trolley is -12 kg·m/s

e. The velocity of the 3 kg trolley = -4 m/s

Explanation:

a. The total momentum of the trolleys which are at rest before the separation is zero

b. By the principle of the conservation of linear momentum, the total momentum of the trolleys after separation = The total momentum of the trolleys before separation = 0

c. The momentum of the 2 kg trolley after separation = Mass × Velocity = 2 kg × 6 m/s = 12 kg·m/s

d. Given that the total momentum of the trolleys after separation is zero, the momentum of the 3 kg trolley is equal and opposite to the momentum of the 2 kg trolley = -12 kg·m/s

e. The momentum of the 3 kg trolley = Mass of the 3 kg Trolley × Velocity of the 3 kg trolley

∴ The momentum of the 3 kg trolley = 3 kg × Velocity of the 3 kg trolley = -12 kg·m/s

The velocity of the 3 kg trolley = -12 kg·m/s/(3 kg) = -4 m/s

a-The total momentum of the trolleys before separation=0

b.The total momentum of the trolleys after  separation=0

c. The momentum of 2kg trolley after  separation=12kg-m/sec

d. The momentum of 3kg trolley after separation=-12kg-m/sec

e. The velocity of the 3kg trolley=4kg-m/sec

Given-

Trolley A with mass= 2kg

Trolly B with mass= 3kg

Velocity of trolly A =6m/sec

A- Total momentum of the trolleys before separation-

Here, in this problem both the trolleys are in the rest position hence the momentum of both trolleys = 0

B- Total momentum of the trolleys after  separation-

We know that motion never changes in an isolated collection of objects,

hence the momentum of the trolleys before and after the separation=0

C- Momentum of the Trolley A (2kg)-

It is known that momentum= Mass x Velocity

\(P=m\times v\)

\(P=2\times 6\)

\(P=12\)

Hence, the momentum of the 2kg trolley is 12 kg-m/sec

D- Momentum of the Trolley B (3kg)-

As we know that  motion never changes in an isolated collection of an object hence the total moment of after saparation = 0

hance the momentum of the trolley B will be equal and opposite to the momentum of trolley A=

\(P= -12\)

Momentum of trolley B (3kg) is -12kg-m/sec

E- The velocity of the 3kg trolley-

The momentum of trolley A= Momentum of trolley B

\(m_{b} v_{a} =m_{b} v_{a}\)

\(-2\times 6=3\times v_{a}\)

\(v_{a}=-4\)

The value of the velocity of the 3kg trolley is -4m/sec

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(a) The initial temperature is 373.95 K.

(b) The final temperature is 546.15 K.

(c) The total internal energy change of the fluid during this process is 515.4 kJ.

(d) The process can be represented as an isochoric heating process on the P-v diagram and as an isobaric expansion process on the T-v diagram.

(a) To find the initial temperature, we can use the saturated steam tables. At a pressure of 200 kPa, the corresponding saturation temperature is 373.95 K.

(b) Since the volume doubles, the process is an isochoric (constant volume) heating process. Using the ideal gas law, we can determine the final temperature. The initial and final volumes are related by the equation V_final = 2V_initial. Since the mass remains constant, the specific volume (v) is inversely proportional to the density (ρ). Therefore, ρ_final = ρ_initial/2. Using the ideal gas law, we can calculate the final temperature to be 546.15 K.

(c) The total internal energy change can be calculated using the equation ΔU = mC_vΔT, where m is the mass of the fluid and C_v is the specific heat at constant volume. Given the mass as 0.5 kg, the specific heat of water at constant volume, and the temperature change, we can find that the total internal energy change is 515.4 kJ.

(d) On the P-v diagram, the process is represented as a vertical line at 200 kPa, indicating constant pressure. On the T-v diagram, the process is shown as an upward-sloping line, indicating an isobaric expansion process. The initial state is represented as a point on the left, and the final state is represented as a point on the right. The path between the initial and final states is a straight line connecting these two points.

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Answer:

women... men

Explanation:

Answer:

c. women... men

Explanation:

edge 2021

The use of energy for the purpose to boil water and warming the environment are the proper use of this lost energy.

The energy which is lost from the bulb is in the form of thermal energy. This thermal energy can be used to boil water or heating the surrounding environment so in this way the lost energy can be used properly.

So we can conclude that use of energy for the purpose to boil water and warming the environment are the proper use of this lost energy.

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We will have that the picture that shows the highest average kinetic energy is image B.

To connect the wires in a 110 block and trim off the excess at the same time, use a punch down tool with a notched blade and point the cut side of the tool towards the wire end.

A 110 block is used to terminate wiring in a cabling system. It is a type of punch down block. This block has a plastic base and have 50 slots for individual wires, meaning it can terminate 25 pairs.

A punch down tool is used insert wire into insulation displacement connectors present in punch down blocks such as 110 block and also in other electrical panels and modules.

Therefore, to connect the wires in a 110 block and trim off the excess at the same time, use a punch down tool with a notched blade and point the cut side of the tool towards the wire end.

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approximately 2.093 x 10^(-6) cubic meters (or 2.093 milliliters) of coffee has spilled out of the beaker.To calculate the volume of coffee that has spilled out of the beaker, we can use the concept of thermal expansion. The change in volume is given by the formula ΔV = βVΔT, where β is the coefficient of volume expansion, V is the initial volume, and ΔT is the change in temperature.

First, let's convert the initial volume to cubic meters: V = 0.858 x 10^(-3) m^3.
Next, we calculate the change in temperature: ΔT = 90.6 - 18.2 = 72.4 °C.
The coefficient of volume expansion for water (and coffee) is approximately β = 3.4 x 10^(-4) °C^(-1).
Plugging in these values into the formula, we get:
ΔV = (3.4 x 10^(-4) °C^(-1)) * (0.858 x 10^(-3) m^3) * (72.4 °C) = 2.093 x 10^(-6) m^3.

Therefore, approximately 2.093 x 10^(-6) cubic meters (or 2.093 milliliters) of coffee has spilled out of the beaker.

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The time that is saved by speeding past the school, endangering pedestrians and risking an expensive fine and poor insurance rating is 0.061 mins.

We define the speed as the ratio of the distance to the time. We know that when a body is in motion, the distance of the object would change with time. The first thing that we need to do is to convert the  distance to miles.

Given that

1 yard = 5.7 * 10^-4 miles

150 yards =  150 yards  * 5.7 * 10^-4 miles/ 1 yard

= 0.0855 miles

Thus;

Speed = distance/time

If he drives at the 35 mph speed;

Time taken =  0.0855 miles/35 mph

= 0.0024 hours or 0.144 mins

If he drives at the 25 mph speed

Time taken =  0.0855 miles/25 mph

= 0.00342 hours or 0.205 mins

Time saved = 0.205 mins -  0.144 mins = 0.061 mins

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Answer:

a = \(-\frac{25}{27}\) m/s²

Explanation:

Acceleration (a) = (final velocity - initial velocity) ÷ (final time - initial time) =  \(\frac{v_{f} - v_{i} }{t_{f} - t_{i} }\)

Converting the speed from km/h to m/s;

100 km = 100000m

1hr = 3600s

∴ 100km/hr ⇄ \(\frac{100000 m}{3600 s}\) = \(\frac{250}{9} m/s\)

Acceleration = \(\frac{0 - 250/9}{30}\) = \(-\frac{250}{9 * 30} = -\frac{25}{27}\) m/s²

i.e deceleration = \(\frac{25}{27}\) m/s²

Mugabe gained power by using political strategies, forming alliances, and exploiting his status as a liberation hero within ZANU-PF.

Robert Mugabe, the former president of Zimbabwe, was able to build power through a combination of political strategies and alliances. One key factor was his involvement in the liberation struggle against white minority rule in Rhodesia (now Zimbabwe).

Mugabe emerged as a prominent figure within the Zimbabwe African National Union (ZANU) party, which later merged with the Zimbabwe African People's Union (ZAPU) to form the Zimbabwe African National Union - Patriotic Front (ZANU-PF). Mugabe's role as a liberation hero and his ability to mobilize support among the majority black population of Zimbabwe gave him a strong power base.

Within ZANU-PF, Mugabe strategically positioned himself and gained influence by forming alliances and outmaneuvering rivals. He rose to become the party's leader and played a key role in negotiating the Lancaster House Agreement in 1979, which paved the way for Zimbabwe's independence in 1980. Mugabe became the country's first prime minister and later transformed the position into an executive presidency, consolidating his authority.

Mugabe maintained power through various means, including controlling key institutions such as the military, intelligence agencies, and the ruling party. He also utilized patronage networks, distributing resources and positions to loyal supporters within the party and government. Mugabe's policies, such as the controversial land reform program, further solidified his power base by appealing to nationalist sentiments and redistributing land from white farmers to black Zimbabweans.

However, Mugabe's consolidation of power was also marked by authoritarianism, human rights abuses, and a declining economy. His grip on power faced challenges over the years, including opposition movements, internal party factions, and economic crises. Ultimately, his rule came to an end in 2017 when he was ousted from power following a military intervention.

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Answer:

The volume of water displaced by the raft is 0.233 m³

Explanation:

The question relates to Archimedes' principle which states that the buoyant force experienced by an object immersed in a fluid is equal to the weight of (the force of gravity on) the displaced fluid

The given parameters are;

The combined mass of the person and the raft, m = 233 kg

The liquid on which the raft is located = Water

The density of water, \(\rho _{water}\) = 1000 kg/m³

Weight = Mass, m × g

Where;

m = The mass of the object

g = The acceleration due to gravity = 9.8 m/s²

Given that the raft is on the surface of the water (floating), the buoyant force is equal to the combined weight of the person and the raft = 233 kg

The combined weight of the person and the raft, \(W_{combined}\) = 233 kg × 9.8 m/s² = 2,283.4 N

Therefore;

The buoyant force = 2,283.4 N = The weight of the water displaced

The mass of the water displaced, \(m_{water}\), = 2,283.4 N/(9.8 m/s²) = 233 kg

Density = Mass/Volume

The volume of water displaced by the raft = The mass of the water displaced/(The density of the water) = 233 kg/(1,000 kg/m³) = 0.233 m³.

Answer:

the volume displaced by the raft = 0.233 m3

Explanation:

correct for Acellus