Answer:
b) the height the ball bounces
Explanation:
the control variable is the variable that you change yourself. since you change the height that the ball bounces from we know this is the answer
A student wants to conduct an experiment to determine the rate at which windows transfer energy to the outside air in the winter. The student investigates windows that are made from two parallel
pieces of class with a space in between as shown in the figure. The student decides to investigate how the spacing between the pieces of glass affects the transfer of energy. Which additional
criteria should the student use when selecting windows for the experiment? Select two answers.
A
Select Windows with different areas
B
Select Windows with the space between the pieces of glass filled with different gases
C
Select windows with pieces of glass made from the same type of glass.
D
Select windows with pieces of glass made from the same thickness of glass,
The characteristics of thermal conductivity and thermal insulation allow finding the correct answers for the window length study experiment to be correct are:
C. Select windows with pieces of glass made from the same type of glass.
D. Select windows with pieces of glass made from the same thickness of glass,
Thermal transfer processes are determined by the characteristics of the materials and their way of construction, but all of them can be described by the expression.
[tex]P = \frac{A}{R} \Delta T[/tex]
[tex]R = \frac{L}{k}[/tex]
where P is the heat flux, A the area of the windows, ΔT the variation in temperature, R is the insulating value of the material, L is the length of the compound and k the thermal conductivity.
Let's examine the criteria that the student must have for the experiment to be repetitive and to be able to compare the results, let's examine the different responses:
A) False. The flow is proportional to the area, so to be able to compare the results, all the windows must have the same area.
B) False. This possibility is interesting, but it is difficult to maintain the different atmosphere besides being expensive, gases in normal conditions have very similar properties.
C) True. The thermal conductivity of different glasses changes a lot, so there should not be different glass in the windows.
D) True. The constant R is proportional to the thickness of the glass, so it is essential that all windows have the same thickness glass.
In conclusion, using the characteristics of thermal conductivity and thermal insulation, we can find that the correct answers for the window length study experiment to be correct are:
C. Select windows with pieces of glass made from the same type of glass.
D. Select windows with pieces of glass made from the same thickness of glass,
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New metals like bohrium our blank or made by people
The figure(Figure 1) shows the angular-velocity-versus-time graph for a particle moving in a circle, starting from θ0=0 rad at t=0s. Draw the angular-position-versus-time graph. Include an appropriate scale on both axes.
Answer:
As position is the product of velocity and time, the area under the velocity-time curve will be the position.
Between 2 and 4 s, the area increases linearly to 20(4) = 80
Between 4 and 6 s, the additional area is 0(2) = 0
Between 6 and 8 s the area increases linearly by -10(2) = -20
which is a decrease.
In the angular-position vs time graph; The angular position is derived from the area under the velocity vs time graph
Attached below is the angular position vs time graph
Given that : Angular position = Angular Velocity * time
As Time increases from 0 to 4 secs the area increases from 0 to 80 rad
As Time increases from 4 to 6 secs the area remains constant i.e. 0 rad
As Time increases from 6 to 8 secs the area under the graph decreases 80 to 60 rad
Hence we can conclude that the Angular position of the graph is derived from the area under the velocity vs time graph.
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simple daily routine ? also add habits to make it healthier
một trái banh đỏ được ném lên từ mặt đất với vận tốc ban đầu 25m/s . cùng lúc đó 1 trái banh xanh được thả xuống từ tầng ba của tòa nhả độ cao 15m. hỏi sao bao lâu 2 trái banh đạt cùng độ sao so với mặt đất
Answer:
Hshahahjahajjajjajaisjsjs
Your new motorcycle weighs 2580 N.
The acceleration of gravity is 9.8 m/s2.
What is its mass?
Answer in units of kg.
Answer:
205 kilograms.
answer ok :)
You skip north for 12 minutes to your best friend's house that is 1.5 kilometers away. What is your average velocity?
Answer:
velocity 2.0 updated sa showbizz happening
What is also a product in the chemical reaction of fusion?
A. Energy
B. Water
C. Sugar
D. Carbon dioxide
Answer:
D.
Explanation:
A
because energy is also a product
In a race, Usain Bolt accelerates at
1.99 m/s2 for the first 60.0 m, then
decelerates at -0.266 m/s2 for the final
40.0 m. What was his final velocity? (Unit = m/s)
A hypothesis is
a type of research method that involves experimentation
a statement describing the actual outcome of an experiment
the question that forms the foundation for a particular study
a statement describing what the researchers expect to find in a study
Help plz
Answer:
A hypothesis is a tentative statement about the relationship between two or more variables. It is a specific, testable prediction about what you expect to happen in a study.
A hypothesis is a tentative statement about the relationship between two or more variables. is a specific, testable prediction about what you expect to happen in a study.
Explanation:
This is answer
Answer:
hey there
hypothesis is a proposed explanation for a phenomenon. For a hypothesis to be a scientific hypothesis, the scientific method requires that one can test it. Scientists generally base scientific hypotheses on previous observations that cannot satisfactorily be explained with the available scientific theories
Explanation:
hope it helps
have a nice day : )
Why would it be better to record larger forces when trying to determine the frictional coefficient between two objects?
có một hiệu điện thế đặt vào ba điện trở mắc nối tiếp nhau R1, R2, R3. Nếu R1 < R2 < R3 thì điện trở nào chịu hiệu điện thế lớn nhất ? Điện trở nào chịu hiệu điện thế nhỏ nhất ?
Answer:
There is a potential difference applied to three resistors connected in series R1, R2, R3. If R1 < R2 < R3, which resistor has the greatest potential difference? Which resistor has the smallest voltage?
Explanation:
What is the change in the internal energy of a system that does 400 joules of
work and absorbs 700 joules of heat?
A. -1,100 J
B. 1,100 J
C. 300 J
D. -300 J
Answer:
B
Explanation:
You want to determine if three different concentrations (25%, 50%, & 100%) are equally effective at inhibiting the growth of Streptococcus in the antimicrobial assay; which of the following statistical tests would be most appropriate to use? a) Student's paired t-test b) t-test for two independent groups c) Analysis of Variance (ANOVA) d) 2x2 contingency table (Chi-squared test)
Answer:
thanks thanks thanks thanks for your points
the speed of the water at the tap of lower storey is more than that in the upper storey,why?
write in one sentence.
Hurry up
With lower, the mechanics have to work harder to give water. Resulting in faster spray. But with upper, they do not have to work as hard which makes it not work as fast.
Pls Help FAST
Brainliest
Answer:
1. S
2.×
3.×
4.×
I hope this can help u
If there is a 25 [lbs] of force acting on a 5 [lbs] of mass, what is the acceleration of that mass?
Answer:
f = 25 lbs
m = 5 lbs
a =?
f = ma
25 = 5 a( divide both sides by 5)
a = 5(lbs)
How to Convert N/m2 to N/cm2 ?
1 newton / square metre =0.0001 newton / square centimetre
Formula = divide the pressure value by 10000
Por una tuberia de 2.65 cm de diámetro fluye agua con una velocidad de 5 m/s; en una parte de la
tuberia hay una reducción en su diámetro de 0.65 cm. ¿Qué velocidad llevará el agua en este punto?
La ecuación de continuidad podemos encontrar el resultado para la velocidad de fluido en la reducción de la tubería es:
v = 83,1 m/s
La mecánica de fluidos estudia el movimiento de líquidos y gases por diferentes sistemas, la conservación de la masa es escrita como la ecuación de continuidad
A₁ v₁ = A₂ v₂
Donde los subíndices son en dos puntos de interés, A el área de la tubería y v la velocidad del fluido.
Indican la velocidad de fluido es v₁ = 5 m/s y el diámetro de la tubería es d₁= 2,65 cm, piden encontrar la velocidad en la parte con un diámetro de d₂ = 0,65 cm
El área de la tubería es
A = [tex]\pi ^r^2 = \pi \frac{d^2}{4}[/tex]
[tex]v_2 =\frac{A_1}{A_2} \ v_1 \\v_2 = ( \frac{d_1}{d_2} )^2 \ v_1[/tex]
Calculemos
v₂ = [tex]( \frac{2.65}{0.65} )^2 \ 5[/tex]
v₂ = 83,1 m/s
En conclusión usando la ecuación de continuidad podemos encontrar el resultado para la velocidad de fluido en la reducción de la tubería es:
v = 83,1 m/s
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help huhuhuhuhuhuhuhu
What is the mass of a truck if it produces a force of 14,000 N while accelerating at a rate of 5m/s2
Answer:
F= mass× acceleration
14000 = mass × 5
mass= 14000÷5
mass= 2800
All ball is thrown up with a vertical velocity of 54 m/s and a horizontal velocity of 39 m/s. Calculate how many seconds it will take for it to reach its peak (assume no air resistance). (Answer to two decimal places).
5.5 s
Explanation:
The time it takes for the ball to reach its maximum height can be calculated using
[tex]v_y = v_{0y} - gt \Rightarrow t = \dfrac{v_{0y}}{g}[/tex]
since [tex]v_y = 0[/tex] at the top of its trajectory. Plugging in the numbers,
[tex]t = \dfrac{(54\:\text{m/s})}{(9.8\:\text{m/s}^2)} = 5.5\:\text{s}[/tex]
Write 1,000,000w
1,000m
0.001 cm using scientific notation
Answer:
1×10^6 w
1×10^3 m
1×10^(-3) cm
Each of the rods depicted below were machined from same stock metal. They were originally machined to be the same length, but their cross-sectional areas were different. If axial force is applied to each rod such that they all change length by the same amount, which rod experienced the largest force
The force required to extend a rod increases as the cross sectional area
increases.
The rod that experiences the largest force is rod B
Reason:
The elongation of a rod by the application of a force is given by the
following formula;
[tex]\Delta L = \dfrac{F \cdot L}{A \cdot E}[/tex]
From the above equation, we have that the elongation is inversely
proportional to the cross sectional area, such that the extension of a rod by
a given force reduces as the cross sectional area of the rod increases.
Therefore, the force required to extend the length of a rod by a specific
amount increases as the cross sectional area of the rod increases,
indicating that the rod with the largest cross sectional area require the
most force and therefore, experiences the largest force.
The rod that experiences the largest force is the rod with the largest cross
sectional area, which is rod B
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how is 1 hectoliter diffrent from 1 kiloliter
An aluminum sphere is 8.20 cm in diameter. What will be its % change in volume if it is heated from 30∘C to 150 ∘C ?
Answer:
Change in volume / volume = 3 K change in temperature
K = 24E-6 / deg C coefficient of linear expansion
R = 4.1 cm
dR / R = 24E-6 * 120 dec C = 2.88E-3
V = 4/3 pi R^3
dV = 4 pi R^2 dR
dV / V = 3 dR / R = 2.88E-3 * 3 = 8.6E-3 = .86%
The percentage change in volume of the aluminum sphere at the given cubic expansivity is 0.9%.
Expansion of the aluminum sphereThe percentage change in the volume of the aluminum sphere is determined by applying cubic expansivity formula of the aluminum.
Initial volume of the sphereV₁ = ⁴/₃πr³
where;
r is the radius = ¹/₂ (8.2 cm) = 4.1 cm = 0.041 mV₁ = ⁴/₃π(0.041)³
V₁ = 2.887 x 10⁻⁴ m³
[tex]\beta = \frac{\Delta V}{V_1 \Delta T}[/tex]
where;
β is cubic expansion of aluminum = 75 x 10⁻⁶/⁰C[tex]\Delta V = \beta V_1 \Delta T\\\\\Delta V = (75 \times 10^{-6} )(2.887 \times 10^{-4})(150 - 30)\\\\\Delta V = 2.6 \times 10^{-6} \ m^3[/tex]
Percentage change in volume of the sphere[tex]\% (V)= \frac{\Delta V}{V_1} \times 100\%\\\\\% (V)= \frac{2.6 \times 10^{-6}}{2.887 \times 10^{-4}} \times 100\%\\\\\% (V)= 0.9 \ \%[/tex]
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What does the scientific method help test in environmental science?
Edmentum/Plato answer please
Answer:
The scientific method helps test and arrive at conclusions for a variety of hypotheses that are created when studying environmental science.
Explanation:
What is the scientific method in environmental science?
The scientific method is a method of research with defined steps that include experiments and careful observation. One of the most important aspects of this method is the testing of hypotheses by means of repeatable experiments. A hypothesis is a suggested explanation for an event, which can be tested.
An airplane makes a gradual 90 turn while flying at a constant speed of 200 m/s. The process takes 20.0 seconds to complete. For this turn the magnitude of the average acceleration of the plane is
Answer:
Explanation:
The plane travels a distance of 200 m/s(20.0 s) = 4000 m
A 90° turn is π/2 radians
4000 = (π/2)R
R = 8000/π m
a = v²/R = 200²/8000/π = 5π m/s² ≈ 15.7 m/s²
When a airplane makes the graduall 90 turn at constant speed the average acceleration is 14.14 m/s.
What is acceleration?Acceleration equals the change in velocity. The rate of change of velocity per unit time is called acceleration. The unit of acceleration is m/s². It represents the speed of the object along with direction.
Acceleration(a) = dv/dt, dv represents change in velocity and dt represents change in time. Velocity is defined as rate of change of position with time. Acceleration has both magnitude and direction and it is a vector quantity.
Acceleration is of two types- Instantaneous acceleration and average acceleration. Instantaneos acceleration gives the acceleration at that instant where as the average acceleration is obtained by rate of change of velocity with elapsed time.
Average acceleration = Δv / Δt. Δv is the change in velocity and Δt is the elapsed time.
From the given,
An airplane makes 90° turn,
v₁ = 200 i^ (before 90 turn)
v₂ = 200 j^ (after 90 turn)
Δt = change in time
Average acceleration = Δv / Δt
= v₂ - v₁ / 20
= 200 i^ - 200 j^ /20
avg.acc = 10(-i) + 10 (j)
| avg.acc | = √ 10(-i) + 10 (j)
= √2×10
= 14.14 m/s²
Hence, the average accleration is 14.14 m/s².
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Вариант 3.
1. Можно ли считать Землю материальной точкой при определении длины экватора Земли? Ответ поясните
Answer:
Для ответа на этот вопрос нужно открыть терадочку в том месте, где ты записывала определение материальной точки. На случай, если ты этот момент успешно проспала (что не стало бы сюрпризом), поясню - материальной точкой можно считать тело, размерами которого можно пренебречь. А теперь скажи мне, как можно измерить размер, которым пренебрегаешь?
which of the following is not a pure substance. A. air B. water C. gold D. glucose
Answer:
C. Gold
Explanation:
Why?
Because air , water, glucose is pure substance or liquid