Answer:
7.5 N/m
Explanation:
Potential energy of a spring can be calculated using below formula
Potential energy= 1/2kx^2
potential energy = 60 J
X= displacement = 4 m
K= spring constant=?
Substitute the values we have
60= 1/2 × K × 4^2
60= 1/2 × K × 16
60= K × 8
K= 7.5 N/m
Hence, the spring constant of the spring is 7.5 N/m
A student is sitting in a chair and not moving, however, there are forces acting on her. What must be trust about the forces acting on the student?
Answer: It is trusted that the sum of all forces acting on the student, adds up to zero the student is not moving.
Explanation: the plane they give you that the plane is moving at a constant velocity of 250 m/s this means that the acceleration is zero, we substituted in the formula F=ma which will give us the Force. And knowing that its constant speed, forward force is then equal to the Air resistance. Hence we find the Air resistance force
A 90° elbow in a horizontal pipe is used to direct water flow upward at a rate of 40 kg/s. The diameter of the entire elbow is 10 cm. The elbow discharges water into the atmosphere, and thus the pressure at the exit is the local atmospheric pressure. The elevation difference between the centers of the exit and the inlet of the elbow is 50 cm. The weight of the elbow and the water in it is considered to be negligible. Determine (a) the gage pressure at the center of the inlet of the elbow and (b) the anchoring force needed to hold the elbow in place. Take the momentum-flux correction factor to be 1.03 at both the inlet and the outlet.
Answer:
(a) The gauge pressure is 4,885.3 Pa
(b) The anchoring force needed to hold the elbow in place is approximately 296.5 N
The direction of the anchoring force is approximately ≈ 134.8
Explanation:
The given parameters in the fluid dynamics question are;
Pipe elbow angle, θ = 90°
The mass flowrate of the water, [tex]\dot m[/tex] = 40 kg/s
The diameter of the elbow, D = 10 cm
The pressure at the point of discharge of the fluid = Atmospheric pressure
The elevation between the inlet and exit of the elbow, z = 50 cm
The weight of the elbow and the water = Negligible
(a) The velocity of the fluid, v₁ = v₂ = v is given as follows;
ρ·v·A = [tex]\dot m[/tex]
v = [tex]\dot m[/tex]/(ρ·A)
Where;
ρ = The density of the fluid (water) = 997 kg/m³
A = The cross-sectional area of the of the elbow = π·D²/4 = π×0.1²/4 ≈ 0.00785398163
A = 0.00785398163 m²
v = 40 kg/s/(0.00785398163 m² × 997 kg/m³) ≈ 5.1083 m/s
Bernoulli's equation for the flow of fluid is presented as follows;
[tex]\dfrac{P_1}{\rho \cdot g} +\dfrac{v_1}{2 \cdot g} + z_1 = \dfrac{P_2}{\rho \cdot g} +\dfrac{v_2}{2 \cdot g} + z_2[/tex]
v₁ = v₂ for the elbow of uniform cross section
P₁ - P₂ = ρ·g·(z₂ - z₁)
P₁ - P₂ = The gauge pressure = [tex]P_{gauge}[/tex]
z₂ - z₁ = z = 50 cm = 0.5 m
∴ [tex]P_{gauge}[/tex] = 997 kg/m³ × 9.8 m/s² × 0.5 m = 4,885.3 Pa
The gauge pressure, [tex]P_{gauge}[/tex] = 4,885.3 Pa
(b) The forces acting on the elbow are;
[tex]F_{Rx}[/tex] + [tex]P_{gauge}[/tex]·A = -β·[tex]\dot m[/tex]·v
[tex]F_{Ry}[/tex] = β·[tex]\dot m[/tex]·v
∴ [tex]F_{Rx}[/tex] = -β·[tex]\dot m[/tex]·v - [tex]P_{gauge}[/tex]·A
[tex]F_{Rx}[/tex] = -1.03 × 40 kg/s × 5.1083 m/s - 4,885.3 Pa × 0.00785398163 m² ≈ -208.83 N
[tex]F_{Ry}[/tex] = 1.03 × 40 kg/s × 5.1083 m/s = 210.46196 N
The resultant force, [tex]F_R[/tex], is given as follows;
[tex]F_R[/tex] = √([tex]F_{Rx}[/tex]² + [tex]F_{Rz}[/tex]²)
∴ [tex]F_R[/tex] = √((-208.83)² + (210.46196)²) ≈ 296.486433934
Therefore;
The anchoring force needed to hold the elbow in place, [tex]F_R[/tex] ≈ 296.5 N
The direction of the anchoring force, θ
[tex]\theta = tan^{-1}\left( \dfrac{F_{Ry}}{F_{Rx}} \right)[/tex]
∴ θ = arctan(210.46196/(-208.83)) = -45..2230044°
θ = 180° + -45.2230044° = 134.7769956°
∴ The direction of the anchoring force is approximately, θ ≈ 134.8°
number of atoms of each element potassium chlorate?
Please help me and get 15 points and Brainlessly!!!!!!!
Bauxite is the chief ore from which aluminum is extracted. Which of these statements is correct about bauxite? (15 points)
Group of answer choices
It has a definite crystal structure.
It does not have a definite chemical composition.
Its atoms do not arrange themselves in a definite order.
Its molecules are made up of a different number of atoms.
Answer:
A
Explanation:
Bauxite is the primary mineral from which aluminum is produced. The ore must first be cleaned before the metal can be electrolytically reduced out of it. Thus, option A is correct.
What Bauxite is the chief ore from which aluminum?Bauxite normally has a Mohs hardness of 1 to 3 and is a soft substance. Its color ranges from white to gray to reddish-brown and has a pisolitic structure. It also has an earthy gloss and a specific gravity of 2.0 to 2.5. These characteristics help distinguish bauxite, although they have no bearing on its worth or potential uses.
Typically, aluminum is manufactured in regions with relatively low electricity costs. An abrasive substance is bauxite.
Therefore, Bauxite is crushed to a fine powder and then fused at a very high temperature to form spherical beads, creating sintered bauxite, which is frequently used as a sand-blasting abrasive.
Learn more about Bauxite here:
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I need help with this question it's science
An alien from the newly discovers planet nine weighs himself on his planet and finds his weight to be 3200 N. When he stoves on earth he once again weighs himself and find his aight to be 800 N. What is the acceleration due to gravity on planet 9?
Answer:
2.45 m/s²
Explanation:
From the question,
On the Earth
W = mg.................. Equation 1
Where W = weight of the alien on the earth, m = mass of the alien on the earth, g = acceleration due to gravity of the earth.
Make m the subject of equation 1
m = W/g................... Equation 2
Given: W = 3200 N
Constant: 9.8 m/s²
Substitute these value into equation 2
m = 3200/9.8
m = 326.5 kg.
Similarly,
On planet 9,
W' = mg'............... Equation 3
Where W' = weight of the alien on planet 9, g' = acceleration due to gravity on planet 9.
make g' the subject of the equation
g' = W'/m............ Equation 4
Given: W' = 800 N
Substitute into equation 4
g' = 800/326.5
g' = 2.45 m/s²
Which statement compares the attractive forces that hold particles together?
A. Covalent bonding and Van der Waals forces join separate
molecules together, while ionic and hydrogen bonding produce
compounds.
B. Covalent and hydrogen bonding produce compounds, while ionic
bonding and Van der Waals forces join separate molecules
together.
C. lonic and covalent bonding produce compounds, while hydrogen
bonding and Van der Waals forces join separate molecules
together.
D. Ionic and covalent bonding join separate molecules together, while
hydrogen bonding and Van der Waals forces produce compounds.
Answer:
Ionic and covalent bonding produce compounds, while hydrogen bonding and Van der Waals forces join separate molecules together.
Ur welcome:)
Answer:
C) lonic and covalent bonding produce compounds, while hydrogen bonding and Van der Waals forces join separate molecules together.
Explanation:
If a car accelerates from rest at a constant 4 m/s
, how long will it take for the car to reach a
velocity of 28 m/s?
Answer:
Time, t = 7 seconds.
Explanation:
Given the following data;
Initial velocity = 0m/s (since it is starting from rest).
Acceleration, a = 4 m/s²
Final velocity, v = 28 m/s
To find the time, we would use the first equation of motion given by the formula;
V = u + at
Substituting into the formula, we have;
28 = 0 + 4*t
28 = 4t
Time, t = 28/4
Time, t = 7 seconds.
I WILL GIVE U BRAINLIST layers: Earth:: ___: the Sun
A: Milky Way galaxy
B: Zero gravity
C: Solid surface
D:Gas
Answer:
There are layers on the Earth. There is gas on the Sun.
This means that the answer is...
D: Gas
A submarine dives at an angle of 30.0o with the horizontal and follows a straight-line path for a total distance of 50.0 m. What distance is the submarine below the surface of the water?
Answer:
25 m
Explanation:
The submarine dives at angle of 30 degree with the horizontal . It has travelled 50 m at this angle . So , it will have both 25 horizontal as well as vertical displacement below the surface .
vertical displacement below the surface = vertical component of displacement of 50 m
= 50 sin30
= 25 m .
Depth of submarine below the surface = 25 m.
What is the name of the force that opposes, or the opposite of gravity ???!!
Answer:
Tension.
tension is the name of force that opposes or goes opposite of gravity
Hope this helps!
Answer: Friction
Explanation: Friction opposes gravity and any motion in two surfaces.
Hope This Helped, Have A Great Day!
Someone help me extra points & brainlest
Answer:
75 m
Explanation:
What is the frequency of a light with the wavelength of 5.00 x 102 m?
Answer:
510 meters
Explanation:
That is sort of a math question but with the meters and wavelength, it's both a physical and a math question. Don't worry, i won't report (Unless you report my answer)
A plane travels 4.0 km at an angle of 25◦ to the ground, then changes direction and travels 10 km at an angle of 16◦ to the ground. What is the magnitude of the plane's total displacement? Answer in units of km.
Answer:
6.1 km
Explanation:
Given that a plane travels 4.0 km at an angle of 25◦ to the ground, then changes direction and travels 10 km at an angle of 16◦ to the ground. What is the magnitude of the plane's total displacement? Answer in units of km
The magnitude of the total displacement D can be calculated by using cosine formula
Ø = 25 - 16 = 9 degree
D^2 = 4^2 + 10^2 - 2 × 4 × 10 × cos 9
D^2 = 16 + 100 - 80cos9
D^2 = 116 - 79.02
D = sqrt( 36.98)
D = 6.1 m
Therefore, the magnitude of the plane's total displacement is 6.1 km
PLEASE HELP!! THIS IS DUE TODAY!
explain how the path of light changes as it moves from the oil to the water
A5.0 kg TNT explosive, initially at rest, explodes into two pieces. One of the pieces weighing 2.0 kg flies off to
the left at 36
What is the final speed of the remaining piece?
Answer:
v = 24 m/s, rightwards
Explanation:
Given that,
The mass of TBT explosive = 5 kg
It explodes into two pieces.
One of the pieces weighing 2.0 kg flies off to the left at 36 m/s. Let left be negative and right be positive.
The law of conservation of momentum holds here. Let v be the final speed of the remaining piece. So,
[tex]5\times 0=2\times (-36)+3\times v\\\\-72=-3v\\\\v=24\ m/s[/tex]
So, the final speed of the remaining piece is 24 m/s and it is in the right direction.
What are some ways scientists can study the seafloor?
Answer: A device records the time it takes sound waves to travel from the surface to the ocean floor and back again. Sound waves travel through water at a known speed. Once scientists know the travel time of the wave, they can calculate the distance to the ocean floor.
Explanation:
Which of the following statements about Australian football is TRUE?
A.
The players tend to wear a large amount of padding.
B.
Goals are scored by kicking the ball through goalposts.
C.
Each team has a number of set plays for both offense and defense.
D.
The constant movement of the ball is similar to baseball.
Answer:
B.
Goals are scored by kicking the ball through goalposts.
Explanation:
What kind of energy involves the flow of positive charges?
thermal
radiant
electrical
nuclear
Answer:
Electrical
Explanation:
Electrical would be the energy that involves the flow of positive charges.
Which formula represents the law of conservation of energy?
Answer:
KE+PE
Explanation:
Marcus tries to move a refrigerator but can't. Has he done work?
A) Yes, because he used energy.
B) Yes, because he exerted a force.
C) No, because he did not move the object.
D) No, because he did not use energy.
Answer:
A
Explanation:
Even if the refrigerator did not move he still used energy to try to push it it's just his energy wasnt stronger than the refrigerator's energy
what does point c represent
Explanation:
point c is minimum Amplitude in transversal wave
which diagram represents the greatest magnitude of displacement for an object
Answer: if every arrow=1m do 1 times 1 times 1 times 1
Explanation:
(p.s. it equals 1 meter in area 4 meters in perimeter)
the unit of force is the
backhaus
Einstein
newton
kilogram
Answer:
the answer is a C a newton
What might you be doing if you measure your heart rate and find that it beats 100 times in a minute?
Answer:
Rigorous exercise
Explanation:
For your heart rate is been around 100 bpm you should be doing a rigorous exercise . but if ain't doing any rigorous exercise and your heart rate is constantly above 100 bpm you should consult your doctor.
An average heart is between 60 bpm to 100 bpm.
can someone help me with this please what are the two correct answers??
Answer:
The answers should be B and D
Explanation:
I hope this helps!
i need help with this question really urgent
Answer:
Cost Per Hour:
132.0000
Cost Per Day:
39600.0000
Cost Per Month:
1204632.00
Cost Per Year:
14455584.00
kWh Per Day:
3600.00
Explain how air exerts a pressure
air exert a pressure take a glass and put the water on it and small piece a paper and glass take downword and observe it so tha air exert pressure
Why do Tectonic Plates move?
A) convection currents in the atmosphere
B) convection currents in the crust
C) convection currents in the asthenosphere
D) Convection currents in the core
Answer:
c. convection currents in the asthenosphere
Explanation:
Someone help me & extra pointsss!
Answer:
117.43 m
Explanation:
Eg=mgh=13x9.81xh=127.53h(N)
Ek=0.5mv^2=0.5(13)(48)^2=14,976 N
by conservation of potenial energy:
Ei=Ef
127.53h=14976
h=117.43m