the total number of x-rays emitted from an x-ray tube could be determined by adding together the number of x-rays emitted at each energy over the entire spectrum, a process called integration.

It can be concluded that at one time in the past, South America and Africa were once one. Beside of the same type of plant foil on the eastern coast of South America and western coat of Africa, we can identify other similar reason that the coastlines of South America and Africa on opposite sides of the Atlantic Ocean seem to fit together.

Yes, is it. Let's back to 1915, a German scientist named Alfred Wegener, proposed that continents could move around on the earth’s surface. He said that in the past there is a supercontinent in the earth named Pangea Continent. Not only South America and Africa, but also all of the continents were all together in the past.

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-20 mph is the the relative velocity of  vba

Va=30 mph

Vb=10 mph

Vab= Vb - Va = 20 mph

Vba=Va - Vb= -20 mph

An object's relative velocity is the speed at which it moves in relation to another object. It serves as a method of determining how swiftly two objects are traveling with respect to one another. Relative velocity is essential to comprehending physics because it helps us grasp how objects move and interact with one another. Relative velocity can be estimated for a variety of interactions. An object's relative velocity is the speed at which it moves in relation to another object. It serves as a method of determining how swiftly two objects are traveling with respect to one another. Relative velocity is essential to comprehending physics because it helps us grasp how objects move and interact with one another.

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Three problems faced by Mark Watney are :

What did Mark Watney do on Mars?

Mark Watney was also selected to perform experiments on plant growth using Martian Soil and Martian gravity.

Why was Mark Watney left on Mars?

Watney gets stranded on the Red Planet when a massive dust storm gravely injures him and forces his crewmates to escape, leaving him dead.

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The change in momentum of the cart is 24 kg⋅m/s.

What is momentum?

A particle's linear momentum, p, when it is travelling at a certain speed is described as

                                                          p = mv

When two objects collide, a force is applied for a predetermined period of time, changing the momentum of the item. When a force acts for a predetermined period of time, the object's mass either increases or decreases (or changes direction).

Given in the question,

Mass of the cart = 1.0 kg

Initial velocity of the cart, vi = 12 m/s

Final velocity of the cart, vf = 12 m/s

The magnitude of the cart's momentum change is

      Δp= m∣νi − νf∣

           = (1 .0 kg)∣(12.0m/s)−(−12.0m/s)∣

           = 24 kg⋅m/s.

Hence, The change in momentum of the cart after collision with the wall is 24 kg⋅m/s.

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The magnitude of the centripetal force acting on an object traveling in a horizontal, circular path is  increases mass, velocity and radius of the path.

centripetal force:

It is a type of force which acting on a object on circular path that keeps the object moving on that path.

Centripetal force is calculated as:

F = 1/2(mv²)

where,

F = centripetal force

m = mass of the object

v = velocity of the object.

From the above relation centripetal force is directly proportional to the mass and velocity and inversely proportional to the radius.

The given question is incomplete. The complete question is

Which of the following would increase the magnitude of the centripetal force acting on an object traveling in a horizontal, circular path?

The magnitude of the centripetal force acting on an object traveling in a horizontal, circular path is  increases mass, velocity and radius of the path.

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The most likely correct about the three stars is: They do not have the same initial mass.

The Chandrasekhar limit is established at a mass where the gravitational field's self-attraction cannot be balanced by the pressure from electron decay.  The limit that has been established these days is 1.39 solar mass.

Hence,  stars of average masses ends by forming white dwarf or neutron star but massive stars ends their life by forming black hole. Hence, They do not have the same initial mass.

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Explanation:

Select the type or types of energy the ball has at the top of the hill.

gravitational potential energy

Select the type or types of energy the ball has halfway down the hill.

gravitational potential energy

rotational kinetic energy

kinetic energy

Select the type or types of energy the ball has on the level ground.

kinetic energy

Cotivational Kinitics Energy

Explanation:

Equal but in opposing directions, forces of the car and the force of the bus.

Given that both objects are moving, you can be sure that the collision is elastic and that the forces involved in the collision between the bus and the car will be equal.

Without force, objects cannot be moved, stopped, or changed direction. Force can be defined as the pushing or pulling of any object as a result of the object's interaction or movement. In nature, there are various types of forces that interact quantitatively between two physical bodies, such as an object and its surroundings. If an object is in motion or in a static state, the position of the object can only be changed by an external force—referred to as force—pushing or pulling against it. The various types of contact force include spring force, applied force, air resistance force, normal force, tension force, friction force, and others that are generated when we exert some effort on an object. Non-contact forces, which include electromagnetic, gravitational, and nuclear forces, are another category of forces that exist at a distance.

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Electromagnetic radiation consists of electromagnetic field waves that propagate through space and carry electromagnetic radiation energy. These include X-rays, gamma rays, microwaves, infrared rays, light, and radio waves. In the electromagnetic spectrum, all of these waves are included.

For the wavelength:

Wave A has four crests, thus its wavelength can be calculated as follows:

λ = L/4

Where, λ = wavelength of a wave

L = total length of wave (1.6 × 10⁻³ m)

λ = 1.6 × 10⁻³ /4

λ = 4.1 × 10⁻⁴ m

Wave B has eight crests, thus its wavelength can be calculated as:

λ = L/8

Where, λ = wavelength of the wave

L = total length of wave (1.6 × 10⁻³ m)

λ = 1.6 × 10⁻³/8

λ = 2.0 × 10⁻⁴ m

This, explains that wave A has a higher wavelength.

Also, the wavelength in the range of 10⁻⁴m corresponds to the infrared region.

For the frequency:

ν = c/λ

Where, ν = frequency

c = speed of light (2.99 × 10⁸ m/s)

λ = wavelength

Wave A has a wavelength of 4.1 × 10⁻⁴ m, so the frequency of the photon will be:

ν = 2.99 × 10⁸/4.1 × 10⁻⁴

ν = 7.49 × 10¹¹ s⁻¹

Wave B has a wavelength of 2.0 × 10⁻⁴ m, so the frequency of photon will be:

ν = 2.99 × 10⁸/2.0 × 10⁻⁴

ν = 1.49 × 10¹² s⁻¹

Hence, wave B has a higher frequency.

For photon energy:

E = hν

Where, E = photon energy

h = plank's constant (6.626 × 10⁻³⁴ Js)

ν = frequency

Wave A has a frequency of 7.49 × 10¹¹ s⁻¹:

E = (6.626 × 10⁻³⁴)(7.49 × 10¹¹)

E = 4.96 × 10⁻²³ J

Wave A has a frequency of 1.49 × 10¹² s⁻¹:

E = (6.626 × 10⁻³⁴)(1.49 × 10¹²)

E = 49.93 × 10⁻²² J

Hence, wave B has greater energy.

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According to Einstein's general theory of relativity, curved spacetime is what causes gravity.

However, gravity a force in the broadest sense since it defines the interaction that results when two masses are in close proximity to one another. The warping of spacetime and also the motion of things through the stretched spacetime are the primary causes of gravitational effects. It appears as though a force was exerted towards the end, though.

With the publication of his general theory of relativity in 1915, Albert Einstein provided the solution. All mass-bearing things, such as the Earth, really bend and curve spacetime, which is what causes gravity to draw you toward the earth. You experience gravity because of its curvature.

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The work energy of speed is 1304.2.

What is work energy?
Work energy is the most fundamental quantity of physics. Work is said to be done when a force applied to an object cause a displacement of a object.

Solution -
As per the given-
Mass of runner m = 74kg
Initial velocity of runner u=4.8 m/s
Final velocity of runner v =0
Coefficient of friction ¥=0.7
Let's d be the distance moved by runner till the stop.
a- mechanical energy lost due to friction
As friction does negetive work causing the runner to stop.
As we know,
Mechanical energy lost= Kinetic energy of runner
Mechanical energy lost = 1/2 mv^2 = 1/2 ×74×4.8^2=852.2

Distance move by runner- Work done by friction = mechanical energy lost
-¥×mg×d =852.2 j
-0.7×74×9.8×d = -491.2
Solving the equation we get
1304.2.

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A 750kg car with an acceleration of 7.8m/s^2 will be as fast as 54.6m/s when it travels for 7 seconds.

It is a rate at which velocity changes with time, in terms of both speed and direction. A point or an object moving in a straight line is accelerated if it speeds up or slows down.

How to calculate the speed of 750kg car when traveling in 7 seconds?
Vf = Vo + a*t

Vo = initial speed = 0 (the car is at rest at a red light)

Vf = final speed

a = acceleration = 7.8m/s^2

t =time = 7s

Vf = Vo + a*t

Vf = 0 + 7.8 * 7
Vf = 54.6m/s

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The old kettle with a power rating of 1.4kw, and the one with a power rating of 2.0kw. With this condition, this will affect the time it takes to boil a fixed volume of water quicker than before.

In electrical engineering and mechanical engineering, the power rating of equipment is the highest power input allowed to flow through particular equipment. According to the particular discipline, the term power may refer to electrical or mechanical power.

How does power rating affect the time it takes to boil a fixed volume of water?

Since, the power rating is higher, logically it has higher power than before. Since it is a fixed volume of water, so the only difference is power rating. With greater power, it will take shorter amount of time to boil the same water by volume.

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The astronomer on duty going to have a bit of a problem satisfying her request after a white dwarf cools off it turns too bloodless and darkish to emit visible light.

According to astronomers, The fate of the left-over center relies upon its mass. If the left-over middle is about 1. four to 5 instances the mass of our solar, it'll crumble right into a neutron big name. If the middle is bigger, it's going to crumble right into a black hollow.

The growth and contraction of pulsating variables may be measured with the aid of using the Doppler effect. The traces inside the spectrum shift in the direction of the blue because the floor of the megastar moves in the direction of us after which shifts to pink as the floor shrinks again. Gold is uncommon in the course of the Universe as it's a tremendously hefty atom, such as seventy-nine protons and 118 neutrons.

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Since the majority of objects in the world do not emit their own light, they must reflect light in order to be seen. The walls of the room you are in reflect the light from the overhead ceiling "lights," not producing any of their own light.

We can only see when light is emitted from the things and strikes our eyes. Some objects, which do not all have the ability to emit light on their own, reflect light. We perceive an object when light strikes it and is reflected back to us by the object's surface.

what is reflection?

Light rays' direction changes and they turn around when they hit an item. This is referred to as light reflection. Incident rays are any rays that land on a surface. The point of incidence is the location at which an incident ray falls.

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Since the majority of objects in the world do not emit their own light, they must reflect light in order to be seen. The walls of the room you are in reflect the light from the overhead ceiling "lights," not producing any of their own light.

What is reflection?

Light rays' direction changes and they turn around when they hit an item. This is referred to as light reflection. Incident rays are any rays that land on a surface. The point of incidence is the location at which an incident ray falls.

We can only see when light is emitted from the things and strikes our eyes. Some objects, which do not all have the ability to emit light on their own, reflect light. We perceive an object when light strikes it and is reflected back to us by the object's surface.

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The ratio of output power for the two turbines is:

P₁/P₂ = 8.87³/ 8.34³

P₁ = 1.203 P₂

Power, the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt, which is equivalent to 1 joule per second. Power is a scalar quantity.

Now let's discuss about the mentioned case:

For flat agricultural land:

Given,

Height (h₁) = 100 m

Wind velocity = 10 m/s

Height of wind turbines (h₂) = 40 m

For flat agricultural land let's consider the roughness to be of class 1.

So, f₀ = 0.03 ( coefficient of friction)

∴ v₂ = v₁ × ln (h₂/f₀) / ln (h₁/f₀)

= 10 × ln(40/0.03) / ln(100/0.03)

= 10 × 7.195/8.112

= 8.87 m/s

For forest land:

Given,

Height (h₁) = 100 m

Wind velocity = 10 m/s

Height of wind turbines (h₂) = 40 m

For forest and let's consider the roughness to be of class 3.

So, f₀' = 0.4 ( coefficient of friction)

∴ v₂' = v₁ × ln (h₂/f₀') / ln (h₁/f₀')

= 10 × ln(40/0.4) / ln(100/0.4)

= 10 × 4.605/5.521

= 8.34 m/s

Now, power output (P): ¹/₂ ρAv³C

Where, P = power

ρ = density of air

A = swept area

C = power coefficient

v = wind speed

P₁/P₂ =  ¹/₂ ρAv₂'³C / ¹/₂ ρAv₂'³C

P₁/P₂ = 8.87³/ 8.34³

P₁ = 1.203 P₂

P₁ = Power of wind turbine in flat agricultural land

P₂ = Power of wind turbine in forest

Using above explanation we can conclude that the wind turbine in flat agricultural land produces more power than the wind turbine in forest.

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The energy emitted by a photon is equal to 7,72 × 10⁻¹⁰ J.

To answer this sola we use the photon energy formula:

E = h(c/λ)

Where:

Once the values ​​are known, enter them into the formula:

E = h(c/λ)

[tex]E = 6,6 * 10^{-34} \frac{6*10^{14} }{5,1 *10^{-10}}[/tex]

[tex]E = 6,6 * 10^{-34}(1,17 *10^{24})[/tex]

[tex]E = 7,72*10^{-10} J[/tex]

So, we can conclude that the approximate energy of one photon of this light is 7,72 × 10⁻¹⁰ J.

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Answer:

Example for 1. Law of Inertia

Falling forward while getting down from a moving bus:

When a passenger gets down from a moving bus, their upper body is still in motion, and when it comes in contact with the ground which is at rest, their body topples forward due to the inertia of motion.

Example for 2. Law of Acceleration

Hitting a Ball:

A ball develops a certain amount of acceleration after being hit. The acceleration with which the ball moves is directly proportional to the force applied to it. This means that the harder you hit the ball, the faster it will move

Example for 3. Law of Interaction

Walking:

Whenever people walk, their foot exerts a force on the ground. The ground then exerts an equal force which points in the opposite direction. It is this force (force due to friction) that allows the person to move forward.

Example for 4. Work and Power

As P=F.v

Cycling:

A person riding a bicycle possesses some amount of energy. This energy is utilized by the cyclist to do work on the paddles of the bicycle by applying some force and enabling the bicycle to move forward.

Example for 5. PE to KE

An apple hanging on a tree:

It has the potential energy due to its raised position. When the apple falls from the tree. The falling apple has the kinetic energy. Thus the potential energy stored in the apple in its raised position changes into the kinetic energy when the apple is falling. This kinetic energy does work on stone as the apple strikes the stone, and it makes the stone to move into the ground.

Example for 6. Sound and Light

TV:

We see TV takes electrical energy as input and produces. light energy, sound energy.

Example for 7. Heat and Electricity

The electric heaters:

An electric heater is an electrical device that converts an electric current into heat.

This statement is FALSE, the visible surface of the sun is composed of solid matter.

The sun is made totally out of plasma, the fourth nation of depending after gasoline, liquid, and strong, and the most energetic. As you could consider, the sun is tremendously hot. It varies among nine,900-27,000,000°F in temperature among the “surface” (the outer limb of its environment where it becomes obvious to light as opposed to opaque), and the middle.  

Unlike the gasoline massive planets, which probably have a strong middle, the sun is made nearly out of hydrogen and helium, the lightest of all the elements, and at no point, internal should either of those exist as a solid at the one’s temperatures, despite the awesome pressures that exist in the solar. It’s plasma all the way down, even at the center where the density is ten instances that of gold.

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One of the key areas of science is the study of acceleration and deceleration. Any object's rate of changing velocity is referred to as its acceleration, and a negative acceleration value is referred to as deceleration.

Using beginning velocity of 50 miles per hour,

It's going to

Final speed: 73.33 ft/s, v = 0, and a2: -22 ft/s2.

Utilize the formula: v2 = v0 + 2as

n 0 = 5377.29 + (-44) s

s =5377.29/44 = 122.21 ft

v2 = u2 + 2as is the third equation of motion. We are already aware that distance is equal to average velocity times time. Either v2 = u2 + 2as or 2as = v2 - u2. The third equation of motion connects the particle's final velocity (v), initial velocity (u), constant speed (a), and displacement (S).

Speed is defined as the ratio of distance travelled to the amount of time required to cover that distance.

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In general, collapse causes central heating, which ultimately causes temperatures conducive to hydrogen ignition. Particularly, material from the molecular cloud's outer reaches transforms gravitational potential energy into kinetic energy as it falls inward toward the cloud's core when gravity outweighs pressure.

The material is either added to the central protostar or spun out into the protoplanetary disc when it reaches the centre of the cloud, converting its kinetic energy into thermal energy. As more material is added, the protostar gets hotter and brighter.

When the centre of the object reaches temperatures of 10-15 million K and nuclear fusion starts, its central pressure and temperature likewise rise. Other angular momentum-related processes shape the material surrounding the collapsing core in the interim and regulate the volume of material engaged in the collapse.

what is kinetic energy?

Kinetic energy is a type of energy that is present in every object or particle that is moving. When work, which entails the exchange of electrons, is done on an object by applying a net force, that object acquires kinetic energy.

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A dense core of material in a molecular cloud begins to collapse due to gravity.

What is gravity?
Gravity is indeed a fundamental interaction in physics that causes all objects with mass or energy to attract one another. The electromagnetic force, the weak interaction, and the strong interaction are all significantly stronger than gravity, which is by far the weakest of a four fundamental interactions. As a result, this has no appreciable impact on subatomic particle level phenomena. However, at the macroscopic level, gravity is the most important interaction between objects and governs the movement of planets, stars, galaxies, or even light. The Moon's gravity causes sublunar tides in the oceans, just as gravity on Earth gives weight to physical objects.

As it collapses, it heats up and the central regions become hotter than the surrounding material. This causes the central regions to become more dense and the surrounding material to be expelled. The star continues to collapse and heat up until it reaches the main sequence, where it stabilizes and begins to produce energy through nuclear fusion.

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(a) The time taken for the ball to reach the maximum height is 1 second.

(b) The maximum height reached by the ball is 25 m.

The time taken for the ball to reach the maximum height is calculated as follows;

h = -16t²  +  32t  +  9

dh/dt = -32t + 32

dh/dt = v

where;

at maximum height, the final velocity, v = 0

0 = -32t   +  32

32t = 32

t = 32/32

t = 1 s

The maximum height reached by the ball is calculated as follows;

h = -16t²  +  32t  +  9

h = -16(1)²  +  32(1)  +  9

h = 25 m

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The magnitude of the induced voltage in the coil is 0.25 V. The induced emf will be strong enough to counteract the underlying voltage shift.

Lentz's Law states that a coil will create or induce a back emf of V if a voltage of V is applied to it when it is not carrying any current. The same holds true if a coil is already carrying current; the back emf will then adapt to any applicable change in voltage (V) for the same reason. The voltage in inductors can be discontinuous, but the current is always a continuous function of time.

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93.6 joule is the energy if source emit in one hour and its power output remains constant

I= 0.026 W/m^2

t= 3600 sec

power= energy/time

energy=power×time

energy= 0.026×3600

energy=93.6 joule

Energy is the ability to perform work in physics. Different shapes, such as potential, kinetic, thermal, electrical, chemical, radioactive, etc., may be assumed by it. Other instances of energy being transmitted from one body to another include heat and work. Energy is always distributed after it has been transferred in accordance with its type. Thus, heat transfer could result in thermal energy, whereas work could result in mechanical energy.

Motion is a trait shared by all forms of energy. For instance, if a body is moving, it possesses kinetic energy. Due to the object's design, which integrates potential energy, a tensioned object, such a spring or bow, has the ability to move even when at rest.

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Radiation dosage is usually measured in rads.

When ionizing radiation enters a human body or object, it stores energy. The energy absorbed by exposure to radiation is called dose. Radiation dose size is expressed in three ways: absorbed, equivalent and effective.

The energy absorbed by the human body after being exposed to radiation is called the absorbed dose. Absorbed dose is measured in units called Grays (Gy). A dose of 1 Gray corresponds to 1 Joule of energy stored in 1 kilogram of matter. Radiation has always been around us. In fact, life evolved in a world containing significant amounts of ionizing radiation. It comes from space, earth, and even from within our own bodies. Natural background radiation doses vary by location and habits.

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Forces can be divided into primarily into two types of forces: Contact Forces. Non-contact Forces.

In physics, pressure is an influence that can trade the motion of an item. A force can reason an item with mass to exchange its velocity (e.g. transferring from a country of rest), i.e., to boost up. force can also be described intuitively as a push or a pull. A pressure has each importance and route, making it a vector quantity. it's far measured in the SI unit of newton (N). force is represented by way of the image F (previously P).

The unique form of Newton's 2d law states that the internet force appearing upon an object is equal to the fee at which its momentum changes with time. If the mass of the item is constant, this law means that the acceleration of an item is at once proportional to the net force performing on the item, is in the path of the net force, and is inversely proportional to the mass of the object.

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a) there is a proportional relationship between the amount of time and distance from a lightning strike.

b)The distance from the lightning strike is 4,116 meter.

The speed of sound in air = 343 meters per second

Time to see lightning  = 12 second.

a)Time and distance are directly proportional to each other.

as we know:

distance = speed  x time

distance ∝ speed

distance ∝ time

b)The distance can be calculated as :

Distance = Speed x Time

Distance = 343 x 12

Distance = 4,116 meter.

a) there is a proportional relationship between the amount of time and distance from a lightning strike.

b)The distance from the lightning strike is 4,116 meter.

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There have 3 forces acting on the helicopter.

There have 2 forces acting on the load.

Magnitude of net force = 200 N.

Magnitude of acceleration of the system = 0.0833  m/s².

The speed of the system is increasing.

Given parameters:

Mass of the helicopter, M = 2000 kg

Mass of the load; m = 400 kg

Thrust force; F =  26000 N.

Hence, there have 3 forces acting on the helicopter:  weight of the helicopter, weight of the load, and thrust.

There have 2 forces acting on the load: weight of the load and thrust.

Total mass of the system = M +m = 2000 kg + 400 kg = 2400 kg.

Magnitude of net force = Thrust - weight of the system

= F - (M + m)g

= 26000 - (2000 + 400) × 10

= 200 N.

Magnitude of acceleration of the system = Magnitude of net force / Total mass of the system

= 200/2400 m/s².

= 0.0833  m/s².

Hence, the speed of the system is increasing.

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The density of the wood from the floor is 2.8 kg.

What is buoyancy force?

A thing's propensity to float in a liquid is called buoyancy. When there is gravity present, all liquids and gases pull anything submerged in them upward with a force known as the buoyant force. An object submerged in a static fluid will float because of the pressure differences acting on its opposing sides.

What is density?

The definition of density for a solid substance is its mass per unit volume. The equation for density is d = M/V and stands for density, mass, and volume. Density is commonly measured in grammes per cubic centimeter.

Apply particle in equilibrium model, to the system of the wood cube and lead block in the vertical direction.

∑fy= B-m wood* g-mg=0

we know

B(buoyant + force)d water L^3 g

Where L^3 is the volume of displaced water

d water L^3 g- m wood*g-mg=0

now density (d)= mass(m)/volume(v)

d water L^3- d wood  L^3- m =0

solve for m

m= d water  L^3- d wood L^3

m=(d water- d wood) L^3

m=(1-0.65)(20)^3

m=2.8 kg

Therefore, density of the wood from the floor is 2.8 kg.

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