A wooden plank 2 m long, 30 cm wide, and 40 mm thick floats in water with 10 mm of its thickness above the surface. What is the mass of the board? The answer is 18 kg
I am trying to figure out how they got that answer.
I know that d = m/v and in order to get mass you use m = d(v). Where does the 10 mm come into play. Also the denisty of water is 1.00 x 103 ... do I use that? I keep getting a ridiculous answer. Any help would be highly appreciated!

The velocity of the crate is 12 m/s and kinetic energy of the crate at the bottom of the ramp is 144.06 J.

Given that,

Weight of the crate = 20 N

Length of the ramp = 3 m

Inclination of the ramp with horizontal = 30°

The friction between the ramp and the crate = 6 N

Potential energy of the crate at the top = 20 * 3 sin 30° = 30 J

Energy lost due to friction = 6 N* 3 m = 18 J

Let the speed of the crate at the bottom be v.

Applying the law of conservation of energy,

30 - 18 = 1/2* (20/9.8)* v²

(12* 24)/2.04 =  v²

v² = 141.18

v = 11.88 m/s ≈ 12 m/s

The kinetic energy of the crate at the bottom of the ramp = 1/2* m* v²

⇒ 1/2* (20/9.8)* 141.18 = 144.06 J

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In order to increase the temperature of an ideal gas in a cylinder that is initially at room temperature, the statement that correctly indicates the appropriate action is to push the piston in rapidly. The temperature of the gas will increase because no energy will be transferred to the surrounding by cooling. (Option C)

An ideal gas refers to a theoretical gas which is composed of many randomly moving point particles that are not subject to interparticle interactions. The concept is useful as it obeys the ideal gas law, which is a simplified equation of state, and is amenable to analysis under statistical mechanics. For an ideal gas, as the temperature increases, the average kinetic energy increases as does the velocity of the gas particles hitting the walls of the container. The force exerted by the particles per unit of area on the container is the pressure, so as the temperature increases the pressure must also increase. Hence, when the piston is compressed so quickly that there is no time to exchange heat to the surrounding, the temperature of the gas increases rapidly.

Note: The question is incomplete. The complete question probably is: A student wants to increase the temperature of an ideal gas in a cylinder that is initially at room temperature. The cylinder has a movable piston with negligible friction. Which of the following correctly indicates an action the student could take to increase the temperature of the gas and why does the temperature increases? A) Pull the piston out rapidly. The gas will expand violently and increase in temperature B) Pull the piston out slowly. The gas will have time to absorb energy from the surroundings by heating as it expands. C) Push the piston in rapidly. The temperature of the gas will increase because no energy will be transferred to the surrounding by cooling. D) Push the piston in slowly. The gas will have time to absorb energy from the surroundings by heating as it is compressed

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A newly discovered planet has twice the mass and three times the radius of the earth. The free-fall acceleration at its surface, in terms of the free-fall acceleration g at the surface of the earth is  2/9 g

The acceleration an object experiences as a result of gravitational force is known as acceleration due to gravity. M/s² is its SI unit. Its vector nature—which includes both magnitude and direction—makes it a quantity. The unit g stands for gravitational acceleration or free-fall acceleration . At sea level, the standard value of g on earth's surface is 9.8 m/s².

The free fall aceleration can be calculate as follows:

The acceleration due to gravity on Earth is

g= GM

      R²

The acceleration due to gravity on the new planet is

gₙ= G2M

     (3 R)²

gₙ= G2M

     (3 R)²

Dividing the two equations we get

          G2M

gₙ =      9 R²     =    2 g

g        GM              9

            R²

Therefore,  the free-fall acceleration at its surface, in terms of the free-fall acceleration g at the surface of the earth is  2/9 g.

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The value of the angular acceleration of the rod is approximately equal to 0.0055 rad/s².

To find the angular acceleration of the rod, we need to first determine the torque acting on the rod around the nail. The torque is given by the formula:

torque = force * distance * sin(angle)

Where: 'force' is the applied force F, 'distance' is the distance between the point where the force is applied and the point around which the torque is calculated (in this case, the nail) and 'angle' is the angle between the force and the distance vector

Plugging in the values, we get:

torque = 0.545 N * 30 cm * sin(40°) = 4.14 N cm

We can then use the formula for torque to calculate the angular acceleration:

torque = moment of inertia * angular acceleration

The moment of inertia of a rod about an end is given by:

moment of inertia = mass * length² / 12

Plugging in the values, we get:

moment of inertia = 50 g * (30 cm)² / 12 = 750 g*cm^2

Solving for angular acceleration, we get:

angular acceleration = torque / moment of inertia = 4.14 N cm / 750 gcm² = 0.0055 rad/s².

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Answer:

Decantation

Explanation:

Immiscible liquids are liquids that are not able to be mixed together to form a homogenous solution. They can often be separated by using techniques such as decantation, in which the liquids are poured carefully so that they form separate layers, or by using a separating funnel, which allows the liquids to be separated by exploiting their differences in densities. Other methods for separating immiscible liquids include filtration, centrifugation, and distillation.

Δh = -13.101 m Far must the pipe drop in height in order to achieve this pressure.

13,101 m must be removed from the height.

Bernoulli went on to say that at whatever point along the fluid flow, the total amount of pressure, kinetic energy, and potential energy per volume is the same.

P+ 1/2 ρv² + ρgh = constant

Given

v = 1 m/s ⇒ constant

P₁ = 101300 Pa (1 atm)

P₂ = 202600 Pa (2 atm)

ρ ethanol = 789 kg/m3

g = 9.8 m/s2

Required

The height(lower level)

Solution

The Bernoulli equation becomes when v₁=v₂ constant

ρgh₁+P₁=ρgh₂+P₂

Solve for the value (height difference):

P₁-P₂=ρgh₂-ρgh₁

P₁-P₂=ρg(h₂-h₁)

(P₁-P₂)/(ρg) = Δh

- 101300 kg/ms² / 789 kg/m³ × 9.8 m/s² = Δh

Δh = -13.101 m

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When a very thin ring is at position x>0 and at distance x along its axis, the gravitational force acting on it is 4GMm/4x2-L2.

With a gravitational pull that diminishes with distance as 1/r2, every body in the cosmos is attracted to every other body. The gravitational force of attraction a body experiences must be proportionate to its mass if two bodies of different masses accelerate at the same rate (i.e., a body twice as heavy experiences twice the gravitational force).

The gravitational force experienced by a minuscule unit mass placed at any point P in space is known as the gravitational field at that point.

Using the equation gravitational potential = GMm/r and further integrating on a short dx length at x from the rod's origin, we may determine this relationship.

U equals GMm/Lln2x-2/2x+2.

separating now with regard to dx, we obtain

F equals 4GMm/4x2L2.

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The horizontal distance the ball travels is 2.209 meters ,if it has velocity of 4 m/s

Given,

velocity (v) = 5 m/s

angle (Θ) = 30+30 = 60

gravitational constant (g) = 9.8 m/s

We know that the distanced travelled by a ball can be find using the  below formulae

distance (D) = v² sin2Θ / g

D = 5²×sin 120 / 9.8

D = 2.209 meters

Aerial distance is the distance between two points or locations that is calculated in the air, as opposed to the ground or a road, which is the route that an aeroplane takes to get from one location to another.

Distance in the air must be measured when flying since it is crucial information for the aviation industry. The nautical mile is a measurement that is widely used to compute distances in space.

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Upward pressure against the bottom is greater than downward pressure against the top of the submerged object.

Buoyant Force:

The upward force applied to an object that is fully or partially submerged in a fluid is known as the buoyant force. Upthrust is another name for this upward thrust. A body submerged partially or completely in a fluid appears to shed weight or to be lighter, due to the buoyant force.

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The force must the player exert to start the sled in motion and keep it in motion is 489.1 Newtons and 455.6 Newtons;

Given values,

Weight of blocking sled = 670 N

Coefficient of static friction between sled and grass = 0.73

Coefficient of kinetic friction between sled and grass = 0.68

a)  Force required to start the sled in motion = Static friction acting on the sled

= coefficient of static friction * weight

= 0.73 * 670

= 489.1 N

b) Force to keep the sled in motion = kinetic friction acting on the sled

= coefficient of kinetic friction * weight

= 0.68 * 670

=455.6N

c) Now,

Total weight = weight of the sled + weight of the coach

where the weight of the coach = mass of the coach * acceleration due to gravity;

= 670 + 100*9.8

=1650

Force required to start the sled and the coach = Static friction acting on the sled and the coach

= 0.73 * 1650

= 1204.5N

Force req to keep the sled and the coach moving = Kinetic friction acting on the sled and the coach

= 0.68 * 1650

= 1122N

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When the ring is stationary, the initial flux, Di, is 0.3713. Final flux, Bi, 2.107*10-3Tm If the ring is there and the difference in flux between the initial and final scenarios is 0.3692 Tm2,

The total number of magnetic field lines passing through a coil or other given area is referred to as initial flux. It is the area's typical magnetic field component that travels through. Flux is modelled mathematically as the surface integral of a vector field, where F is the vector field and d A is the vector area of surface A, directed as the surface normal.

The initial flow is 0.97*0.49, which is 0.371 Tm2.

9.3*10-3T*0.49m2 = 2.107*10-3Tm2 is the final flux.

The flux change is calculated as (0.3713 - 2.107*10-3Tm2 = 0.3692Tm2).

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Answer:

A piece of paper will not produce the same kind of reflection as a mirror. A mirror is a highly polished, smooth surface that is able to reflect light in a way that produces a clear and detailed image. A piece of paper, on the other hand, is a rough and porous surface that is not able to reflect light in the same way. When light hits a piece of paper, it is absorbed by the fibers and absorbed, scattered, and absorbed again in multiple directions, which produces a diffuse and distorted reflection. Therefore, a piece of paper will not produce the same kind of reflection as a mirror.

(a) According to you, your player finishes the symphony first.

(b) According to the observer on the train, the observer's player finishes the symphony first.

Because of the variables in the given problem move relative to one another. The person standing next to the track is travelling at a much slower relative speed than the one seated on the train since the train is moving at a much higher speed. In this scenario, the clock that is located in the train will be operating at a slower rate in comparison to the frame of reference that is considered to be stationary.

So, according to you, your player finishes the symphony first. Ans according to the observer on the train, the observer's player finishes the symphony first.

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The acceleration of the elevator when the scale reads 400 N is 0.18m/[tex]s^{2}[/tex] downwards.

The acceleration of the elevator when the scale reads 610 N is 0.04m/[tex]s^{2}[/tex] upwards.

Yes, the student should worry because the elevator is in free fall, that is, there are no supporting cables on the elevator.

The tension in the cable for part A is 450 N.

The tension on the cable for part D is 0.

The given parameters;

When the scale of the elevator reads 400 N, is moving downwards since the apparent weight is less than the real weight

R = mg + ma

400 = 570 + ma

400 - 570  = ma

- 170 = ma

a = [tex]\frac{-170}{m}[/tex] = [tex]\frac{-170}{900}[/tex]  =  0.18m/[tex]s^{2}[/tex] , downwards

so, The acceleration of the elevator when the scale reads 400 N is 0.18m/[tex]s^{2}[/tex] downwards.

The scale of the elevator will read more when it is moving upwards;

610 = mg + ma

610 = 570 + ma

610 - 570 = ma

ma =40

a = [tex]\frac{40}{m}[/tex] = [tex]\frac{40}{900}[/tex]   = 0.04m/[tex]s^{2}[/tex] , upwards

So, the acceleration of the elevator when the scale reads 610 N is 0.04m/[tex]s^{2}[/tex] upwards.

When the scale reads, the upward acceleration is equal to the acceleration due to gravity and the student will be in free fall.

R = m(g - a)

g = a

R = m(0)

R = 0

Thus, the student should worry because the elevator is in free fall, that is, there are no supporting cables on the elevator.

The tension in the cable for part A is 400 N.

The tension in the cable for part D is 0.

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FT​=8278.857 N In the arteries of a man, the pulse wave moves at a rate of 4 to 10 meters per second.Its velocity is somewhat influenced by the blood flow through the artery under consideration

Your pulse is how you can feel your heart rate. Every time your heart beats, it squeezes and propels blood through the network of arteries in your body. Your pulse is the pressure in your arteries going up briefly as your heart pushes out more blood to keep circulation going.

The amplitude, length, & pulse width of a pulse have no effect on its speed.The breadth or length of a pulse changing has no effect on the pulse speed.

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Moon Illusion is an Optical Phenomenon. This occurs because when the moon is near the horizon, Earthly things that resemble the moon on your retina generate a misunderstanding or inaccurate perception of distance and size.

The brain interprets the low moon as being bigger since it is lower in the sky than the higher moon. The mechanism behind size-distance perception in everyday life, which transforms planar pictures that fall on the retina into a perception of hard objects moving in space, is related to the moon illusion.

What happens when the mechanism acts in an uncommon circumstance is what causes the moon illusion. In typical perception, the angular size of the light image stimulating our eyes expands or shrinks as rigid objects move in depth (distance).

The sense of hard objects with shifting depth perception is produced naturally by the brain in response to these changing stimuli. The ground and horizon make the moon appear comparatively close when it is close to the horizon.

Due to the moon's shifting apparent position in depth while the light stimulus stays constant, the moon appears extraordinarily huge due to the brain's size-distance mechanism.

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The trigonal planar shape is consistent with the fact that the CLF3 molecule has a dipole moment.

This shape is formed by three identical polar bonds that are arranged in a flat plane. Each of the three bonds has a slightly negative charge on the chlorine atom and a slightly positive charge on the fluorine atoms. This arrangement of charge creates a permanent dipole moment across the molecule, which is a result of the arrangement of the polar bonds and the molecular structure.

The t-shaped structure, on the other hand, has a single polar bond and two non-polar bonds, which would lead to a net dipole moment of zero, since the charges would cancel out. Therefore, the trigonal planar shape is the most consistent with the fact that the CLF3 molecule has a dipole moment.

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The rings must look much the same today as they did shortly after Saturn formed.

The Rings of Saturn:

The Saturnian ring system is the largest ring system in the Solar System. They are made up of innumerable tiny particles that circle Saturn and range in size from micrometers to meters. With a very small amount of stony material, the ring particles are virtually exclusively formed of water ice. Regarding how they form, there is still no agreement. Newer evidence from Cassini indicates that the rings developed relatively late, despite theoretical models suggesting they were likely to have formed early in the Solar System's history.

It is believed that the fragments of comets, asteroids, or shattered moons that broke apart before they reached Saturn and were blasted apart by the planet's strong gravity make up Saturn's rings. They are composed of countless quantities of tiny pieces of rock and ice that have been dusted with other substances.

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Shift of half a wavelength from the previous part correspond to π radian.

Interference is a phenomenon in which two waves combine by adding  displacement together at every single point in the space and time, to form a resultant wave of greater, lower, or same amplitude.

The superposition principle explains that when two or more waves overlap in space, then the resultant disturbance is equal to the algebraic sum of  individual disturbances

Given, Wavelength= λ

We have to find the phase difference when  wavelength is half of the initial wavelength.

So, the path difference= Δx = λ/2

As, phase difference= 2π/λ * Δx

So, phase difference= 2π/λ * λ/2

Thus, phase difference= π radian

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the pointing vector for the given wave is  [tex]219.26*10^{-9}j[/tex]

Electromagnetic waves, or EM waves, are waves produced by oscillations between electric and magnetic fields. In other words, EM waves consist of oscillating magnetic and electric fields.

The electric and magnetic fields of electromagnetic waves are perpendicular (right angles) to each other. They are also perpendicular to the EM wave direction.

S = (1/μ[tex]_{o}[/tex] )E*B ,

where

μ[tex]_{o}[/tex] is the vacuum permeability;

E is the electric field;

B is the magnetic flux density.

And,

1/μ[tex]_{o}[/tex] [tex]= 7.9*10^{5} units[/tex]

so,

[tex]S = 7.9*10^{5} (-9.13*10^{-3} ) *(-3.04*10^{-11} )[/tex]                               ∵ [tex](kxi = j)[/tex]   [tex]S = 219.26*10^{-9} j[/tex]

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1. The initial velocity required to barely reach the edge of the shell below you is 6.67 m/s.

2.  The projectile will land at 9.54 m of the second cliff d = 9.54 m

1. To find the horizontal velocity of the rock we need to use the following equation:

d = v * t

Where:

d: is the distance traveled by the rock

t: is the time

The time can be calculated as follows:

t = √2d/g

g: is gravity = 9.8 m/s²

t = √2d/g  = 1.20s

Now, the horizontal velocity of the rock is:

v = d/t = 6.67m/s

Hence, the initial velocity required to barely reach the edge of the shell below you is 6.67 m/s.

To calculate the distance at which the projectile will land, first, we need to find the time:

t = √2d/g = 1.43s

the distance is:

d = v * t = 9.54m

Therefore, the projectile will land at 9.54 m of the second cliff.

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The item is lowered 15 cm from its equilibrium point shown above before being let go at time t = 0. The item subsequently begins to oscillate with a 2.0 s period. Assuming that x = 0 represents equilibrium, upward motion is the positive direction.

A sentence's object is the portion on which the verb performs its action. In conventional English, a sentence is usually written with the object coming first. The verb, or what performs the action, is the subject.

Things may be done to objects as well as done to them. A function or method object, for instance, may be coded to change the contents of a data structure or variable.

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The one that is not a suggestion is the number of repetitions should remain the same regardless of the sport's skill. The correct option is c.

An athlete is someone who practices for and participates in sporting activities, either professionally or just for enjoyment. Examples of athletes include those who bowl for a team, run in neighborhood 5K races or take home an Olympic gold medal.

The biggest advantages of imagery are seen in tasks with mostly cognitive components for increasing the learning and performance of motor abilities.

Therefore, the correct option is c, The number of repetitions should remain the same regardless of the sport skill.

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The question is incomplete. Your most probably complete question is given below:

There should be three to four sessions per week.

Sessions should be around 15 minutes in length.

The number of repetitions should remain the same regardless of the sport skill.

If concentration wanes, break imagery sessions into shorter blocks.

Imagery practice should be systematic.

Answer:

North and South poles

Explanation:

The total distance when  the mass slides of 5kg starts from rest at point a and is accelerated by a force of 5N is 50 m.

F=μ.d

ma=μ.d

d=ma/μ

d=5×5/0.5

d=50 m

Distance, which is independent of direction, is the length between two points or things. Distance only considers the total magnitude and disregards the start and finish positions because it is a scalar property. Distance can only have a positive or zero value because it is a scalar attribute; it cannot be negative. The meter (m) is the most widely used unit of measurement for distance, though kilometers (km) can also be used to express longer distances and centimeters (cm) or millimeters can be used to express shorter distances (mm). The distance traveled is frequently represented by the letter D when calculating distance.

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The answer related to Equator of following are : 1) is not, 2) n – mg = may = 0, 3) equator, 4) n – mg = may < 0, 5) larger, 6) equator

What is Equator?
The equator, an invisible circle that spans the centre of the planet and runs parallel to it at its widest point, is located halfway between the North and South Poles. The areas of Earth where the equator crosses are among the warmest because they are closest to the sun.

The equator exists in other places besides just Earth. There is an equator on each planet and star in the sky. An invisible line that lies evenly between the two poles of each rotating planet or star, including the sun in our solar system, is referred to as the equator.

The majority of the equator travels across the ocean, as seen in the image below.

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Centripetal acceleration of cheetah is 21.3 m/s^2. the radius of the turn was approximately 18.9 meters.

To find the centripetal acceleration, we can use the formula a = v^2/r, where a is the centripetal acceleration, v is the velocity of the object, and r is the radius of the turn.

In this case, we are given the mass of the cheetah (45 kg) and the sideways force on its feet (960 N), so we can use the formula F = ma to find the acceleration.

F = ma 960 N = (45 kg)(a) a = 960 N / 45 kg a = 21.3 m/s^2

Now that we have the acceleration, we can use the formula a = v^2/r to find the radius of the turn if the cheetah was running at 20 m/s.

a = v^2/r 21.3 m/s^2 = (20 m/s)^2/r r = (20 m/s)^2 / 21.3 m/s^2 r = 18.9 m

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The flow rate as a function of diameter is Q^2 = 2.24 × 10^-4×D^4 / 10^-4 - D^4 when 0.2 m difference in the manometer level.

Given: The pipe's diameter at point 1 isD1=0.1 m D1=0.1 m

D2=D at point 2 dia. of pipe

And the pipe's flow rate is Q.

Velocity at point 1, where V1=Q/D12/4.

V1= Q/π×(0.1) (0.1)

^2/ 4

Speed at point 2; V2=Q/D2

^2/ 4

As atmospheric pressure causes pipes 1 and 2 to both open, both are 0; 1 and Bernoulli equation application at point 2

P1/pg+v12/2g+ h1= P2/pg+ v22/2g+ H2, where v12 / 2g+ h1= v2 / 2g+ H2.

Put the velocity and height values in the equation above.

Q^ 2/( π/4)^2×(1/D^4-l/(0.1)^4)= 2×g×(h1-h2) (h1-h2)

Q^2 = 2.24 × 10^-4×D^4 / 10^-4 - D^4

This represents the flow rate as a function of diameter.

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An electromagnetic wave's frequency is the same as the frequency of the vibrating charge that causes it. The amount of vibrations, or back and forth motions, that occur in a charge in a second, is known as its frequency.

Electromagnetic waves, often known as EM waves, are waves that are produced when an electric field and a magnetic field vibrate together. In other words, the oscillation of the magnetic and electric fields results in electromagnetic (EM) waves. In contrast to mechanical waves, electromagnetic waves can move through voids. This suggests that electromagnetic waves can travel into empty space in addition to through solid materials like air and rock.

Food-borne microorganisms can be eliminated by the widespread use of electromagnetic radiation in food preparation. Recent research on the microwave or radio wave portion of the electromagnetic spectrum has found promising results for the inactivation of germs in food preparation.

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