I need help with us history

Answer:

a

Explanation:

i took the test 100%

The speed of the block at point B = 6.36 m/s

Given data :

Mass ( m ) = 10 kg

Angle of inclination ( θ ) = 30°

Length of incline = 5 m

Determine the speed of the block at a point B on the incline

First step : Calculate the work done by frictional force

given that there is no friction on the horizontal plane. Vinclined = Vhorizontal

∴ Work done by frictional force ( Wf ) = F * L cos 180

                                                              = - ( μ_k * N ) L

                                                              = - (0.1 * 84.86   ) * 5  = - 42.4 Joule

where N = mg cos 30°

              = 10 * 9.8 * 0.866 = 84.86

Next step : Calculate the speed of the block at point B

applying work energy theorem

Wf = ΔK.E + ΔP.E

     = ( 1/2 mv² - 0 ) + ( 0 - mgh )

∴ - 42.48  = 1/2 mv² - mgh

1/2 mv² = mgh - 42.48

            = 10 * 9.8 * 5 sin 30° - 42.4

       v²  = 40.52

V ( speed of the block at point B ) = 6.36 m/s

Hence we can conclude that the speed of the block at point B = 6.36 m/s

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Attached below is the complete question related to your question

Answer:

n/a

Explanation:

this question is not feasible

Assuming each trial represents 1000years, and rock samples were found, the rock sample will be given half-life of

We know that the parent Isotope remaining is given by the expression

[tex]\frac{1}{2}^n[/tex]

where,

n = number of half lives passed

From the question, the parent Isotope remaining is [tex]25\%[/tex] lokium

[tex]0.25 = \frac{1}{4} = \frac{1}{2^2} = \frac{1}{2}^2[/tex]

Therefore,

[tex]\frac{1}{2}^2[/tex] means 2 half lives have passed.

If from the question,

1 half life = 1000years

Therefore,

The rock sample's age = [tex]2*1000 = 2000years[/tex]

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Answer:False

Explanation:

the intensity of the sound wave decreases with increasing distance from the source.

Answer:

Explanation:

Ignoring friction, the acceleration will double

F = ma

2F = m(2a)

Theprojectile launch allows to find the correct answer for the question about the direction of the ball when it hits the ground is:

       D)  θ = 37º measured clockwise from the x-axis.

projectile launch is an application of kinematics where there is no acceleration on the horizontal axis and the acceleration on the vertical axis is the gravity acceleration.

The horizontal distance traveled until it reaches the ground is

          x = v₀ₓ t

The height of the bullet is

          y = y₀ + [tex]v_o_y[/tex]  t - ½ g t²

The initial vertical velocity is zero and when it reaches the ground its height is zero.

         0 = y₀ - ½ g t²

         t = [tex]\sqrt{\frac{2y_o}{g} }[/tex]  

We substitute

          [tex]x = v_{ox} \ \sqrt{\frac{2y_o}{g} }[/tex]  

They indicate that the distance is:

          x = [tex]\frac{8}{3} \ y_o[/tex]  

We substitute

          [tex]\frac{8}{3} y_o = v_{ox} \sqrt{\frac{2y_o}{g} }[/tex]  

          [tex]v_{ox} = \frac{8}{3} \sqrt{\frac{y_o g}{2} }[/tex]  

The vertical speed when reaching the ground is:

         [tex]v_y = v_{oy} - g t \\v_y = - g t \\v_y = - g \sqrt{\frac{2y_o}{g} }[/tex]

Let's use trigonometry for the direction at the point of hitting the ground.

         tan θ = [tex]\frac{v_y}{v_x}[/tex]  

          θ = tan⁻¹ ( [tex]- \frac{3}{8} \ \frac{\sqrt{2y_o/g}}{\sqrt{y_o g /2} }[/tex] )

          θ = tan⁻¹ ( [tex]tan ^{-1} (- \frac{3}{8} \sqrt{4} )= tan^{-1 } \ (- \frac{3}{4} )[/tex]

          θ = -36.9º

The negative sign indicates that the angle is clockwise from the x-axis.

In conclusion, using the projectile launch we can find the correct answer for the question about the direction of the bullet when it hits the ground is:

      D) θ = 37º measured clockwise from the x-axis.

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Answer:

The first one is the only one that is true all the time

Explanation:

The second one may be true if friction is high enough.

The other three are false all the time

Answer:

I think some drawbacks are that since there are no solid walls meaning it is weak and if murphy's law is in place, the water will destroy the substance. Tsunami waves also happen very quickly so even if the water can travel thru the substance quickly, it probably won't be quick enough. This design could help if the wave is smaller because less destruction would occur.

Explanation:

yeah

Answer:

D. High frequency and short wavelengths.

Explanation:

If a wave is high in energy it will have a higher frequency.

High frequency = short wavelengths

σ = F/A = F/ (πD²/4) = 20000 / (π0.10²/4) = 2.55 MN/m²

An artistic statement should be written from your own perspective.

An artist's statement, also known as an artist statement, is a written summary of their creative output. The brief essay serves as an explanation of and a defense of their own work for the spectator. As a result, it is didactic, descriptive, or reflective in nature and seeks to inform, connect with an artistic environment, and reveal the inspiration behind the work.

The writing created by the artist aims to contextualize, justify, extend, and/or explain their body of work. It situates—or tries to situate—the piece in relation to art history, art theory, the contemporary art scene, and the times. The statement also demonstrates that the artist is aware of their aims, their practice, its place within the parameters of art, and the debate that surrounds it.

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Answer:

measure the area in which the rider will sit on, then take those measurements to a person who crafts saddles, tell them the exact measurements. then you wait a while until he/she is done then put the saddle on the horse.

Explanation:

Answer:

Explanation:

The shape of the horse's withers is also a determining factor in choosing a saddle. An adjustable hoop saddle allows you to choose with finesse the opening of the tree at the height of the withers, in order to best adapt to each horse. It is the size of the arch that determines the opening of the saddle.

English saddles are the main riding saddles used in equestrian disciplines around the world: Show jumping, endurance, require specific designs to meet specific needs. For example, dressage saddles are designed to bring the rider closer to the horse, allowing him to communicate very precisely with his horse.

Answer:

Explanation:

Q1) d) A is not correct; R is correct (sort of) but is not the reason for A.

A vector may be resolved into an infinite number of components.

Breaking a projectile motion into the vertical and horizontal components is the EASIEST way to solve it because acceleration can be assumed to be constant in both directions. Zero for horizontal and g(ravity) in the vertical. However it is not the ONLY way to do it. Other ways are much more complex.

Q2) a) Both A and R are correct; R is the correct explanation of A  (sort of)

A is correct. Speed is constant in uniform circular motion.

R is correct if you call CENTRIPETAL acceleration constant. It is only constant in magnitude. The direction is always changing as the vector always points toward the center of rotation.

Answer:

Explanation:

parallel capacitances add directly

Series capacitances add by reciprocal of sum of reciprocals.

Ceq = [ C ] + [1 / (1/C + 1/C)] + [1 / (1/C + 1/C + 1/C)]

Ceq = [ C ] + [C / 2] + [C / 3]

Ceq = [ 6C/6 ] + [3C / 6] + [2C / 6]

Ceq = 11C/6

Answer:

Cellular respiration that uses oxygen is called ​Cellular respiration

Explanation:

Without oxygen, it's call fermentation.

Answer:

[tex]19.64N[/tex]

Explanation:

Let's remember that if a mass describes a circle of radius [tex]l[/tex] with a constant speed of [tex]v[/tex], it has an angular velocity [tex]\omega=\frac vl[/tex]. in our case, our angular velocity will be of [tex]12/1.1= 10.91 rad/s[/tex].

Now that same mass will be subject of a centripetal acceleration [tex]a_c[/tex], caused of the tension of the string, equal to [tex]a_c=\omega^2l[/tex], which, in our situation, will be [tex](10.91)^2\times1.1=130.91 m/s^2[/tex]

We're almost done. We got mass, we got acceleration, the tension has to be their product: [tex]T= ma=130.91\times0.15=19.64N[/tex]

Answer:

When the input to an inverter is high (1) the output is low (0); and when the input is low, the output is high.

Answer:

Explanation:

PE = mgh

g = PE/mh

g = 15.0 / (0.200(0.500))

g = 150 m/s²

This is one strong astronaut if he can work in an environment where gravity is more than 15 times stronger than on earth.

Answer:

what will happen if i will answer ur questions?

Explanation:

is there gonna be a bad thing or a good thing

Answer:

the wind carries abrasive materials

Explanation:

such as sand and salt over time theses small particles slowly strip way at the land form sculpting it by eroding the softer layers first

The average momentum of Cart 1 during the entire time shown before the collision is 0.24 kgm/s.

The given parameters:

The average velocity of the cart 1 before collision is calculated as follows;

[tex]v = \frac{\Delta x}{\Delta t} \\\\v = \frac{0.55 - 0.31}{0.5 - 0} \\\\v = 0.48 \ m/s\\\\[/tex]

The average momentum of Cart 1 during the entire time shown before the collision is calculated as follows;

[tex]P = mv\\\\P = 0.5 \times 0.48\\\\P = 0.24 \ kgm/s[/tex]

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Answer:

1.108 ×  [tex]10^{-3}[/tex]J

Explanation:

v=21.0v

Q=52.8×  [tex]10^{-6}[/tex]

E=?

V=E/Q

E=v ×Q

 =21 ×52.8 ×[tex]10^{-6}[/tex]

 =1108.8   ×[tex]10^{-6}[/tex]

E= 1.108 ×  [tex]10^{-3}[/tex]J

Answer:

10.5k

Explanation:

1.5x7=10.5

Answer:Progression is the way in which an individual should increase the load. It is a gradual increase either in frequency, intensity, or time or a combination of all three components.

Explanation:

Answer:

n

Explanation:

TWO outcomes can be predicted the students will find:

When a constant mass of gas is cooled, its volume falls, and when the temperature is raised, its volume grows. The volume of the gas rises by 1/273 of its initial volume at 0 °C for every degree of temperature rise.

In layman's words, the volume of a fixed mass of gas is exactly proportional to temperature at constant pressure.

The teacher took two latex balloons and blew them up with helium gas to the same size. As she placed Balloon A in a -15° C freezer, its temperature decreases and that's why, the size of balloon A becomes smaller. Again she  placed Balloon B in the sun on 30° C day, its temperature increases and that's why, the size of balloon B becomes larger.

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Answer:

b rugby and basketball

Explanation:

basket ball was made by a white man

American Football originated from Soccer and Rugby. Hence, option (A) is correct.

American football, sometimes known as gridiron, is a team sport played by two teams of eleven players on a rectangular field with goalposts at each end. It is known simply as football in the United States and Canada. The defense, the team without the ball, seeks to halt the offense's movement and seize control of the ball for themselves.

The offence, the team in possession of the oval-shaped football, attempts to advance down the field by running with the ball or throwing it. The offence is awarded a new set of four downs to resume the drive if they successfully gain at least 10 yards in four downs or plays. If they fail, they forfeit the ball to the defense.

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Answer:

Explanation:

vA / vB = √(TA/(m/L)) / √(TB/(m/L))

The lengths are the same, so the L divides out to 1

The material is identical so the mass will be directly proportional to the cross sectional area of the string

vA / vB = √(TA/(πdA²/4)) / √(TB/(πdB²/4))

π/4 is common so divides out to 1

vA / vB = √(TA/dA²) / √(TB/dB²)

vA / vB = √(410/0.489²) / √(809/1.27²)

vA / vB = 41.407 / 23.396

vA / vB = 1.8488961...

vA / vB = 1.85

Explanation:

We know that,

→ 139 = ½ × m × (8)²

→ 139 = ½ × m × 64

→ 139 = 1 × m × 32

→ 139 ÷ 32 = m

→ 4.34 kg = m

Therefore, mass in kg is 4.34 kg.

Happy Holidays!

Recall the equation for kinetic energy:

[tex]\large\boxed{KE = \frac{1}{2}mv^2 (J)}}[/tex]

m = mass (Kg)

v = velocity (m/s)

KE = kinetic energy (Nm or J)

We can find the kinetic energy for both the bowling ball and baseball:

Bowling ball:

[tex]\large\boxed{KE = \frac{1}{2}(4)(10^2) = 200 J}[/tex]

Baseball:

[tex]\large\boxed{KE = \frac{1}{2}(.25)(50^2) = 312.5 J}[/tex]

Since 312.5 J > 200 J, the BASEBALL has the greater kinetic energy. Thus, it would exert a greater impact force than the bowling ball, so it would hurt more.