which property of electromagnetic waves is least useful when identifying the objects emitting them?
A. Amplitude
B. Frequency
C. Speed
D. Wavelength

The plot depicts the position versus time of a toy car in one dimension. during 4 — 6 seconds and 0—2 seconds intervals is the car going backward.

Time in physics is determined by its measurement. This measurement requires extreme precision, which leads to the requirement that time be considered a linear continuum that is indivisible and not quantized. However, with sophisticated tools, time is now measured accurately using modern atomic time standards such as TAI and UTC.

In classical/non-relativistic physics, time is a scalar quantity and the general concept used is absolute time. Meanwhile, in relativity, time is understood as something relative. In contrast, Quantum Mechanics states that in fact time may not be a central concept in quantum theory as in classical physics and there is actually no such thing as quantum time.

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The magnitude of acceleration will be: [tex]a = \frac{2}{4^2} \left( 200 \text{ ft} - v_0 \cdot 4.0 \text{ s} \right)[/tex]

The magnitude of the acceleration can be found using the equation of motion for the uniformly accelerated motion:

[tex]$$d = v_0 t + \frac{1}{2} at^2$$[/tex]

where d is the braking distance,

v_0 is the initial speed,

t is the time taken to stop, and

a is the magnitude of the acceleration.

Given that the braking distance is 200 ft, and the time taken to stop is 4.0 s, we can write:

[tex]$$200 \text{ ft} = v_0 \cdot 4.0 \text{ s} + \frac{1}{2} a \cdot 4.0^2 \text{ s}^2$$[/tex]

Solving for a, we find:

[tex]a = \frac{2}{4^2} \left( 200 \text{ ft} - v_0 \cdot 4.0 \text{ s} \right)[/tex]

Note that v_0 is not given, so we cannot determine the exact value of a.

However, we can see that the magnitude of the acceleration is proportional to the difference between the braking distance and the product of the initial speed and time taken to stop.

The greater the difference, the greater the magnitude of the acceleration.

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The projectile's displacement horizontally as a result of velocity is shown by the horizontally velocity component (vx). The component of vertical velocity (vy).

The vector's horizontal portion spans from its source to its farthest x-coordinate. From of the x-axis to a vector's highest point, the vertical component runs. The vector and the two parts combine to form a right triangle.

A velocity vector shows the rate of change in an object's position. The magnitude of a velocity vector represents an object's velocity, while the vector's direction represents an object's direction.

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Click Variables on the Designer panel to start. It shows the Variables panel. Enter the name and click the Create Variable line. There is a new variable made.

Drag an activity to the Designer panel from the Activities panel. Create a variable by selecting it from the context menu when you right-click a field or by pressing Ctrl+K. It shows the Set Var field. Enter after entering the name. The created variable is present in the field. In UiPath, there are three ways to generate variables: Open the Variables panel, choose the 'Create new Variable' option, and then fill out the fields as necessary. Give its name in the desired Properties field or Designer panel as necessary.

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The possible values of the velocity vector x component are - 20.71 m/s or 20.71 m/s.

Velocity is a vector quantity so it can be described in x components and y components.

Look at the picture. At quadrant III

At quadrant IV

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There is no such time interval when the particle is not moving during its motion in the y-axis.

The position of the particle in the y axis is give by the relation,

y = 0.20+8t-10t²

Differentiating with respect to time,

dy/dt = 8-20t

Now, we know,

dy/dt = speed

So,

Speed = 8-20t

For not moving the particle should have zero speed at that moment, so putting speed = 0,

8-20t = 0

8 = 20t

t = 20/8

t = 2.5 second

Now, here we are asked of any "interval" now any specific moment where the particle is at rest, because speed is only zero at only one moment, there is no such interval of zero speed, also, it might be possible that at 2.5s the particle is turning so we cannot be sure.

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Complete question - The position of a particle moving along the y axis has a position given by y = 0.20+8t-10t².  Is there a time interval during which the particle is not moving?

When such two balls are moving at the same speed, F1: F2 = 1: 4 will be the ratio of drag forces on balls A and B.

Within science, the term "force" has to have a specific definition. At this point, describing a force as both a push or even a pull is completely acceptable. There is no substance that only an object "seems to have in it" or which it "contains" that is the force. This force is applied to one thing by another. The definition of a force comprises both living as well as non-living things.

Drag force calculation formula is = F(d) = 1/2 * C * rho*A * v²

Drag coefficient, or C

A = object area

rho = density of the moving object

v = the object's velocity

A = the object's area

F1 (force of drag on ball A) = 1/2 * C * rho * area of ball A *  v²

Ball A's drag force, F2, is equal to = 1/2 * C * rho * area of ball B *  v²

The only difference between the two balls is their differences in area because both are falling in the same environment and have the same speed.

F1/F2 = ball area A / ball area B=  4 * pi * r1² / 4 * pi * r2²

r1²/r2²

(d/2)²/(2d/2)²

F1 : F2 = 1 : 4

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Density of the rock after submerging in a beaker of  water is 2.67ˣ10³Kg/m³.

We are given some quantities like Force = 20.0 N,Density = 1000 kg/m³.We need to calculate the mass of the rock firstly when it is reading 20N.

Similarly,the scale new reads 12.5 N,we need to again find the mass of the rock.

Using formula of force,we know that

F=mg

=>20N=m×10

=>m=20/10

=>m=2kg.

Now,Scale reads 12.5 N after rock is totally submerged so mass of rock after submerged.We need to calculate the mass of rock

Using formula of force,

F=mg

=>12.5=m×10

=>m=12.5/10

=>m=1.25Kg.

The scale reads 12.5 N = 1.25 kg so it is displacing 0.75 kg of water

We need to calculate the volume of rock using volume of water it displaces.Since,density is given we need to use the formula of volume which is given by

Volume=mass/density

=>V=0.75/1000

=>V=7.5×10⁻⁴m³

After finding the volume,we need to calculate the density of the rock.

Using formula of density,

density=mass/volume

=>density=2kg/7.5×10⁻⁴m³

=>density=2666.66kg/m³

=>density=2.67ˣ10³Kg/m³

Hence, density of rock is 2.67ˣ10³Kg/m³.

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If both the speed and radius of a circular path of a body  are doubled then centripetal acceleration will also be doubled.

The characteristic of an object moving in a circular path is known as centripetal acceleration. Centripetal acceleration is the term for any moving object whose acceleration vector is directed toward the center of the circle. The centripetal acceleration formula is as follows:

[tex]a_c=v^2 /r[/tex]

where v is the angular speed and r is the radius.

Now for the given question,

Original centripetal acceleration,

[tex]a=v^2 /r[/tex]

New centripetal acceleration,

[tex]a^{'} =(2v)^2 /2r\\\\=2v^2/r\\=2a[/tex]

Hence, centripetal accelearation is also doubled.

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   ​

When conditions and hazards are present on or near a highway, a motorist is not permitted to operate a vehicle there faster than would be reasonable and prudent.

An object's kinetic energy is the force it has as a result of motion. We have to put forth work to apply a force. After the job is finished, the object will be travelling at a new, constant speed because energy has indeed been transferred to it.

Unless otherwise indicated, 80 km/h is the max speed limit in King Edward Island. The standard speed limits are: 40 kilometres (municipalities may choose the top posted speed within their boundaries); 50 kilometres (30 mph) in urban areas; and 60 kilometres (40 mph) in school zones identified as such by the installation of signs at the intersections.

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Answer:

Into thermal energy.

Explanation:

When the breaks are applied, the kinetic energy is converted to heat, meaning it transforms into thermal energy.

The repulsive force between two pith balls is F = 9.8 × 10^(-4) N

It can be calculated using Coulomb's law, which states that the force between two point charges is proportional to the product of the charges and inversely proportional to the square of the distance between them. The formula for Coulomb's law is:

F = k × q1 × q2 / r^2

where k is the Coulomb constant (9 × 10^9 N × m^2 / C^2), q1 and q2 are the magnitudes of the charges, and r is the distance between them. With the given charges of 34.0 nC and a separation of 10.3 cm, we can calculate the repulsive force as follows:

F = (9 × 10^9 N × m^2 / C^2) × (34.0 × 10^(-9) C)^2 / (0.103 m)^2

F = 9.8 × 10^(-4) N

The resulting force will be a positive value, indicating repulsion.

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Answer: Babies inherit their eye color through the combination of genes they receive from their parents. Genes, which are located on chromosomes, determine a specific trait, such as eye color. Each gene has two alleles, one from each parent, and the dominant allele will determine the phenotype, or the observable physical characteristics, of the trait. If a baby inherits a dominant allele for brown eyes and a recessive allele for blue eyes, the brown allele will be expressed, resulting in brown eyes. The combination of alleles a baby inherits is called their genotype. If a baby inherits two identical alleles for a trait, they are said to be homozygous for that trait, while if they inherit two different alleles, they are heterozygous. The dominant allele is expressed over the recessive allele in heterozygous individuals, resulting in a phenotype that reflects the dominant allele.

Explanation:

(A) Apparent weight when the car is at the top of the bump is 388 newton. (B) Speed at which the car loses contact with the bump road is 17.15 m/s.

In science and engineering, weight of an object is defined as the force acting on the object due to gravity.

Given, r = 30 m ; v = 10 m/s and m = 60 kg

A) Let N be normal reaction.

And at the bump

N = mg - mv² / r

N = 60 x 9.8 - 60 x 10 x 10 / 30 = 588 - 200

N = 388 newton

Part B) Then contact loose, N = 0

So, mg = mv² / r

v² = r x g = 30 x 9.8 = 294

v = 17.15 m/s.

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Note: The question given on the portal is incomplete. H. Here is the complete question.

Question: A car moving at a steady 10 m/s on a level highway encounters a bump that has a circular cross-section with a radius of 30 m. The car maintains its speed over the bump. What is the normal force exerted by the seat of the car on a 60 kg passenger when the car is at the top of the bump? Part B) what speed does the car lose contact with the bump road?

Yes, when light is transmitted or reflected, some energy can be absorbed by the medium or the surface it encounters, reducing the intensity of the light. This is why materials can appear to be colored or opaque.

Reflection is an important aspect of seeing, as it enables us to see objects by allowing light to bounce off of them and reach our eyes. Light from a source reflects off its surface, and then enters our eyes, allowing us to perceive the object and its location in space.

Eyes can be damaged in a variety of ways like physical trauma, UV exposure, Infections, Degenerative conditions, chemical exposure, etc.

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The amount of work required to haul up the rope is 30.72 Nm. This can be calculated by multiplying the weight of the rope (0.624 N/m) by the length of the rope (50 m).

The work required to haul up the 50 m length of rope weighing 0.624 N/m is 30.72 Nm. This can be found by using the equation Work = Force x Distance.

The force is the weight of the rope, which is 0.624 N/m, and the distance is the length of the rope, which is 50 m. When multiplied together, the resulting work is 30.72 Nm.

Hauling the rope up will therefore require an expenditure of energy equal to 30.72 Nm.

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We can model this as an infinite square well in which the particle's potential energy inside the box is zero and the potential energy outside is infinite. Therefore, the particle's quantum number is 4.86 × 10⁻²

The expression of wave function for a particle in one dimensional box is given as

φ(x) = ( √2/L ) sin ( nπx/L )

now we input our given figures, the limit of the particle to find it within the center of the box is

xₓ = L/2 + 20% of L/2

xₓ = L/2 + (0.2)L/2

xₓ = 3L/5

And the lower limit is,

x₁ = L/2 - 20% of L/2

x₁ = L/2 - (0.2) L/2

x₁ = 2L / 5

The expression for the probability of finding the particle within the center of the box is

P = ∫ˣₓ₁ ║φ(x)║² dx

P = ∫ ³L/⁵ ₂L/₅║(√2/L) sin ( nπx/L)║²dx

= 2/L ( ∫ ³L/⁵ ₂L/₅║sin ( nπx/L)║²dx

= 2/L ( ∫ ³L/⁵ ₂L/₅ (( 1 - cos ( 2πn x/L)/2) dx)

The particle is in its first excited state, then

n =2

Then calculate  the particle's quantum number as follows;

= 2/L ( ∫ ³L/⁵ ₂L/₅ (( 1 - cos ( 2π(2)x/L)/(2)) dx)

= 1/L ( ∫ ³L/⁵ ₂L/₅ (( 1 - cos ( 4πx/L)/2) dx

= 1/L ( x - (L/4π)sin (4πx/L)) ³L/⁵ ₂L/₅

= 1/L ((3L/5) - (L/4π) sin (( 4π(3L/5)/L)) - (( 2L/5) - (L/4π)sin  ( 4π(2L/5)/L)))

= 1/L ( L/5 + L/4π (sin(8π/5) - sin ( 12π/5)))

Use the trigonometric formula to solve the above equation

Sin A – sin B = 2sin ( A-B/2) cos (A+B/2)

Calculate the particle's quantum number as follows

P = 1/L ( L/5 + L/4π (sin(8π/5) - sin ( 12π/5)))

= 1/5 + 1/4π ( 2sin( (8π/5 -12π/5 ) / 2 ) cos ( (8π/5 + 12π/5) / 2 ))

= 1/5 + 1/2π ( -sin(2π/5) cos2π

= 1/5 - 1/2π ( sin (2π/5)(1))

= 0.0486 (10⁻²)(10²)

= 4.86 × 10⁻²

Therefore, the particle's quantum number is 4.86 × 10⁻²

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The angle of the mountain surface above the horizontal is calculated to be 75°.

Velocity of an object rolled is given as 7 m/s.

Horizontal component of velocity is given as 1.8 m/s.

Drawing a triangle, V becomes the hypotenuse and Vx becomes the adjacent side. We get the formula from that image using the characteristics of a right triangle.

Therefore, cos x = Vx / V.

where, x is the angle we are calculating

The formula's cos x value is obtained by substituting the given values: cos x = 1.8 m/s / 7 m/s = 0.257.

x = cos⁻¹(0.257) = 75 degrees

Thus, the angle of the mountain surface above the horizontal is calculated to be 75 degrees.

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The person has covered a distance of 6m.

Distance is the total length of the path covered by an object, whereas displacement is the change in position of an object from its starting point. In other words, distance is a scalar quantity that refers to "how much ground an object has covered," whereas displacement is a vector quantity that refers to "how far out of place an object is."

For example, if an object moves from point A to point B, the distance covered is the total length of the path from A to B, whereas the displacement is the shortest possible distance from A to B in a straight line. Displacement has both magnitude and direction, while distance only has magnitude.

The distance that has been covered by the person that has been moving can be obtained from;

2 m + 4m

= 6m

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The velocity is 0.43 m/s to the west and difference in Kinetic energy is 1 J.

Together, the arrow and the target have a mass of  7.05 kg.

Using the formula p = mv, and the concept of conservation of angular momentum.

.25 x 12 + 6.8 x 0 = 7.05 x v final.

3 + 0 = 7.05 v,

and v = .43 m/s to the west.

The kinetic energy measured before and after will not be the same.

The value of KE before is [tex]\dfrac{1}{2}(0.25)12^2+ \dfrac{1}{2}(6.8) (0)^2[/tex] = 18 J.

The KE afterward is [tex]\dfrac{1}{2}(7.05)(0.43)^2[/tex],

which equals 0.65 J.

The difference is about 17 J.

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By observing from the equator, you can see all of the stars in the sky at different times of the year, as the earth's rotation and orbit allow you to see different parts of the sky throughout the year.

The equator is an imaginary line that circles the earth, dividing it into two hemispheres: the northern hemisphere and the southern hemisphere. It is the line of zero degrees latitude and is located approximately at 0.00°N latitude. It is about 40,075 kilometers long and is the only line of latitude that is equidistant from both the North Pole and the South Pole. The equator passes through 13 countries including Ecuador, Colombia, Brazil, Congo, and Kenya.

The equator has a unique climate, as it is located in the tropics and receives more direct sunlight than any other part of the earth. This results in a hot and humid climate, with temperatures averaging around 27°C. The equator also experiences frequent rain, with high rainfall levels, particularly in the Amazon Basin. The equator is home to a diverse range of plant and animal life, including tropical rainforests, which are some of the richest and most diverse ecosystems on the planet.

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Explanation:

If the particles of different densities were dropped at the same time from a boat into still water, they would sink or float based on their individual densities. If the denser particles are heavier, they will sink faster than the less dense particles. The less dense particles will float to the surface.

A 20m long metal rod has a radius of 1.0 cm and a resistance of 3.2 x 10-5 ohms. The resistivity of the metal is 5.0 * 10 -8 ohm - m.

The value of the metal's resistivity must be determined in accordance with the question.

resistivity = π* r * R / L

= 3.14 * 0.01 * 0.01 * 3.2*10^-5 / 0.20 m

= 5.0 * 10 ^ -8 ohm - m

The Greek letter omega () represents resistance, which is measured in ohms. Ohms are named after the German physicist Georg Simon Ohm (1784-1854), who studied the relationship between voltage, current, and resistance. Ohm's Law is credited to him.

All materials, to some extent, resist current flow. They are divided into two categories:

Conductors are materials with very little resistance that allow electrons to move freely. Silver, copper, gold, and aluminum are just a few examples.

Insulators: Materials with high resistance to electron flow. Rubber, paper, glass, wood, and plastic are just a few examples.

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The new variable vb is the speed at the bottom of the window, defined by vb = Lw/t + gt/2.

In the problem instead of using LW,

Let us use L alone. h is the height from the bottom of the window to the position where from which the pot was dropped

L = (Vb)t - 0.5gt^2 or (Vb) = (L/t) + 0.5gt

Also (Vb) ^2 =2gh,

Hence 2gh = [(L/t) + 0.5gt] ^2 h = [(L/t) + 0.5gt] ^2/ 2g.

This is the needed equation. This can be modified as

h = (L^2/2gt^2) + (L/2) + (gt^2/8)

b) V-ground^2 - Vb^2 = 2g Hb

V-ground^2 = 2g (h_ total)

= 2g Hb + Vb^2 2g ( h_ total)

= 2g Hb + Vb^2 ( h_ total) = Hb + Vb^2/2g

c) From 1 (Vb)

= (L/t) + 0.5gt

The bottom of the window is at a height Hb above the ground

V-ground^2 - Vb^2

= 2g Hb V-ground^2

= 2g Hb + Vb^2

Substituting for Vb, we get the required equation.

The speed of an item is the significance of the exchange of its role over time or the magnitude of the change of its function in step with a unit of time; it's far thus a scalar amount. The common velocity of an item in an interval of time is the gap traveled with the aid of the object divided via the period of the interval the immediate speed is the restriction of the common velocity as the duration of the time techniques 0. pace isn't similar to speed.

Speed has the size of distance divided by means of time. The SI unit of pace is the meter according to second (m/s), however, the most commonplace unit of speed in everyday utilization is the kilometer in keeping with the hour (km/h) or, inside the US and the UK, miles in line with the hour (mph). For air and marine tours, the knot is commonly used.

The fastest viable pace at which power or information can tour, according to important relativity, is the velocity of mild in vacuum c = 299792458 meters per 2d (about 1079000000 km/h or 671000000 mph). depend can not pretty reach the velocity of light, as this will require an infinite amount of energy. In relativity physics, the idea of rapidity replaces the classical idea of pace.

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All the options given should be part of solving any problem in physics.

Physics problem-solving calls for a methodical and meticulous approach. First and foremost, it's critical to attentively analyze the problem and comprehend the condition presented.

A situational drawing might aid in visualizing the issue and highlighting any crucial elements. Next, it's important to note down each and every variable that the problem provides. The next step is to consider whether physics concepts are applicable to the issue and choose the appropriate equations to apply them.

Once the calculation has been completed, it is crucial to double-check the answer's units to make sure they are formatted correctly. Finally, evaluate the reasonableness of your response and make any required modifications.

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the initial height of the bob of pendulum is approximately 0.9801 m

The following equation can be used to calculate the pendulum bob's initial height:

h = [tex]v^2 / 2g[/tex]

where g is the acceleration brought on by gravity ([tex]9.8 m/s2[/tex]), v is the speed of the bob at the swing's bottom, and h is the starting height.

replacing the specified values:

h = [tex](0.99 m/s)^2 / (2 * 9.8 m/s^2)[/tex]

h = 0.9801 m

As a result, the bob's starting height is roughly 0.9801 m.

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Answer:

Below

Explanation:

Series resistances are additive:    V = IR =  (8.8)(1 + 15+23) = 343.2 v

Energy efficiency refers to the use of less energy to perform the same tasks.

Meanwhile law of conservation of energy states that energy cannot be created or destroyed, only converted from one form to another; a machine's efficiency below 100% does not violate the law of conservation of energy because some energy is inevitably lost as waste heat during energy conversion processes.

Energy efficiency refers to the ability to perform a task using the minimum amount of energy necessary. Energy efficiency is important because it helps reduce the energy consumption and greenhouse gas emissions that result from energy production.

A machine that is not 100% efficient does not violate the law of conservation of energy because energy is not destroyed, only converted from one form to another. When energy is converted from one form to another, some energy is inevitably lost as waste heat. According to the principle of energy conservation, energy can neither be created nor destroyed; rather, it can only be transformed from one form into another.

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The block may move up to 19.7 cm from its resting position, and its oscillations last for a period of 2.76 seconds.

The final position less the starting position is known as displacement.

The greatest displacement is:

The simple harmonic motion equation can be used to determine the block's maximum displacement:

x = A * cos (wt)

where w is the angular frequency, t is the time, and A is the amplitude. The block's starting velocity can be used to compute the amplitude:

A = v0 / w

The spring constant can be used to determine the angular frequency:

Sqrt(k / m) = w

Where k is the spring constant and m is the block's mass.

Replacement of values

A = 50.0 cm/s/sqrt(17.5 N/m/0.800 kg), and w = sqrt(17.5 N/m/0.800 kg).

w = 2.32 rad/s, with A = 19.7 cm

The maximum displacement is equal to the amplitude:

x = A = 19.7 cm

The oscillation's time scale:

The angular frequency can be used to calculate the oscillation's period:

T = 2 * pi / w

Replacement of values

T = 2.76 s = 2.32 rad/s / 2 * pi

Therefore, the oscillation's period is roughly 2.76 seconds.

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The amount of force which is required to be applied on an object to displace it is 1100 Newtons.

Work done can be defined as the force applied to move an object, it should be transferred to the energy of an object. Transferring the energy to an object can be in the method of force.

Work done = effort force × effort arm × cosθ

where, theta is the angle between the effort arm and the load arm. Since the angle is not given, we can assume it to be 90 degrees.

We know that the work done is 400 joules, the effort arm is 10 meters, and the load arm is 2 meters.

We can substitute these values into the equation:

400 = Feffort × 10 × cos(90)

The cosine of 90 is zero.

So, Feffort = 400/0 = undefined

To find the force applied, we can use the principle of the mechanical advantage of the lever.

MA = load arm/effort arm = 2/10 = 1/5

Feffort = Fload / MA = 220 N / (1/5) = 1100 N

Therefore, the force applied must have been 1100 Newtons.

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