Answer:
The critical radius of the plastic insulation is 0.72 inches.
Explanation:
Given that,
Diameter = 0.091 in
Thickness = 0.02 in
Initial temperature = 90°F
Final temperature = 50°F
Heat transfer coefficient = 2.5 Btu/h.ft²°F
Material conductivity = 0.075 Btu/h.ft °F
We need to calculate the critical radius of the plastic insulation
Using formula of critical radius
[tex]r_{cr}=\dfrac{2K}{h}[/tex]
Where, k = Material conductivity
h = Heat transfer coefficient
Put the value into the formula
[tex]r_{cr}=\dfrac{2\times0.075}{2.5}[/tex]
[tex]r_{cr}=0.06\ ft[/tex]
[tex]r_{cr}=0.72\ inches[/tex]
Hence, The critical radius of the plastic insulation is 0.72 inches.
What is the dependent variable in this hypothesis?
After finding that objects of the same mass do not
always float or submerge the same way in a tub of
liquid, Alexis wrote a new hypothesis to test objects that
have the same mass.
o the mass of the object
O the surface area of the object
O the amount of water displaced
O the height at which the object floats
If the surface area of an object increases, then it
will float higher in the tub, because the object
would need to displace more liquid in order to sink
all the way down.
Answer:
The height at wich the object floats
Explain
took on edge 2020
Answer:
the height at which the object floats
Edge 2021
Hitting a ball off a tee would be considered which of the following?
A.
A closed serial skill
B.
An open continuous skill
C.
An open discrete skill
D.
A closed discrete skill
5. Why does a properly adjusted head restraint help prevent head and neck injuries to occupants in
rear-end collisions? Explain your answer in terms of the law of conservation of momentum.
Answer:
Have you tried google
Explanation:
Answer:
protect against whisplasg injuries
Which value represents accuracy: the mean, median, mode, range from center, or distance between farthest beanbags?
Answer:
the mean
Explanation:
The mean (informally, the “average“) is found by adding all of the numbers together and dividing by the number of items in the set: 10 + 10 + 20 + 40 + 70 / 5 = 30. The median is found by ordering the set from lowest to highest and finding the exact middle. The median is just the middle number: 20.
Fossil fuels like gasoline or coal are examples of
Answer:
Nonrenewable Resources
Answer:
fossil fuels
Explanation:
Complete the sentence with the word "element" or "compound." O is a(n) and H2O2 is a(n)
Answer:
O is an element whilst H2O2 is a compound.
Explanation:
O is an element. You can find it on the periodic table. H2O2 is composed of both H and O. Thus, H2O2 is a compound.
The O is a(n) element and [tex]H_{2} O_{2}[/tex] is a(n) compound.
What is element?All facets of a species of atoms with a specific count of protons in its nuclei are referred to as chemical elements, such as the pure substance made exclusively of the that species.
What is compound?A compound comprises a substance created by the chemical fusion of two or more components.
Therefore, the O is a(n) element and [tex]H_{2} O_{2}[/tex] is a(n) compound.
To know more about compound and element.
https://brainly.com/question/13025901
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A nucleus with a mass number of 64 has a mean radius of about: _________.
A. 4.8 fm.
B. 19 fm.
C. 77 fm.
D. 260 fm.
E. 2.6 × 10 5 fm
Answer:
The correct option is A
Explanation:
From the question we are told that
The mass number is [tex]A= 64[/tex]
Generally the mean radius is mathematically evaluated as
[tex]R = R_o A^{\frac{1}{3} }[/tex]
Here [tex]R_o[/tex] is a constant with a value [tex]R_o =1.2*10^{-15}[/tex]
So
[tex]R = 1.2*10^{-15} * 64^{\frac{1}{3} }[/tex]
[tex]R = 4.8 *10^{-15} [/tex]
[tex]R = 4.8\ fm [/tex]
The mean radius of a nucleus with the given mass number is 4.8 fm.
Hence, Option A. 4.8 fm is the correct answer.
Given the data in the question;
Mass number of nucleus; [tex]A = 64[/tex]
Mean radius; [tex]R =\ ?[/tex]
The volume of the nucleus is directly proportional to the total number of nucleons.
The radius of a nucleus, R, is approximately:
[tex]R = R_oA^{\frac{1}{3} }[/tex]
Where R is the radius, R₀ is constant for all nuclei ([tex]1.2*10^{-15}m \ or\ 1.2fm[/tex] ) and A is the mass number.
We substitute our values into the equation
[tex]R = 1.2fm\ *\ 64^{\frac{1}{3} }\\\\R = 1.2fm\ *\ 4\\\\R = 4.8 fm[/tex]
The mean radius of a nucleus with the given mass number is 4.8 fm.
Hence, Option A. 4.8 fm is the correct answer.
Learn more: https://brainly.com/question/1371394
how to find range with height and velocity
Answer:
[tex]R= \frac{ v_ i\: ^2\:\times sin\:20}{g}[/tex]
Explanation:
A small block with mass 0.200 kg is released from rest at the top of a frictionless incline. The block travels a distance 0.394 m down the incline in 2.00 s. The 0.200 kg block is replaced by a 0.400 kg block. If the 0.400 kg block is released from rest at the top of the incline, how far down the incline does it travel in 2.00 s
Answer:
The distance traveled by the second block is 0.197 m
Explanation:
Given;
mass of the small block, m₁ = 0.2 kg
distance traveled by the block, d₁ =0.394 m
time of travel, t = 2 s
mass of the second block, m₂ = 0.4 kg
distance traveled by the second block, d₂ = ?
The work done per unit time on the inclined plane is given by;
[tex]\frac{f_1d_1}{t} = \frac{f_1d_1}{t}\\\\f_1d_1 = f_2d_2\\\\m_1gd_1 = m_2gd_2\\\\m_1d_1 = m_2d_2\\\\d_2 = \frac{m_1d_1}{m_2} \\\\d_2 = \frac{0.2*0.394}{0.4}\\\\d_2 = 0.197 \ m[/tex]
Therefore, the distance traveled by the second block is 0.197 m
The overall length of a piccolo is 30.0 cm. The resonating air column is open at both ends. (a) Find the frequency of the lowest note a piccolo can sound. (Assume that the speed of sound in air is 343 m/s.) Hz (b) Opening holes in the side of a piccolo effectively shortens the length of the resonant column. Assume the highest note a piccolo can sound is 3 000 Hz. Find the distance between adjacent antinodes for this mode of vibration.
Answer:
(a) the frequency of the lowest note the piccolo can sound is 571.7 Hz
(b) the distance between adjacent antinodes is 5.72 cm
Explanation:
(a)
Given;
length of piccolo, L = 30 cm = 0.3 m
the speed of sound in air is 343 m/s
The wavelength of a pipe open at both ends, for the first harmonic is given;
L = A → N + N → A
L = λ / 4 + λ / 4
L = λ / 2
λ = 2L
λ = 2 x 0.3 = 0.6 m
The fundamental frequency (lowest frequency) is given by;
f₀ = v / λ
f₀ = (343 / 0.6)
f₀ = 571.7 Hz
(b)
Given;
highest note, f = 3000 Hz
the distance between adjacent antinodes is given by;
[tex]d = \frac{v}{2f}\\\\ d = \frac{343}{2*3000}\\\\ d = 0.0572 \ m\\\\d = 5.72 \ cm[/tex]
If horizontal velocity is 5 m/s, and vertical velocity is 8 m/s, what is the magnitude of the resultant velocity?
Answer:
40 m/s
Explanation:
Jesse is swinging Miguel in a circle at a tangential speed of 3.50 m/s. If the radius of the circle is 0.600 m and Miguel has a mass of 11.0 kg, what is the centripetal force on Miguel? Round to the nearest whole number. N
Answer:
224.6 N
Explanation:
We can use first the formula to calculate the centripetal acceleration, given by:
[tex]a_c=\frac{v_t^2}{R}[/tex]
where the Vt is the tangential velocity, and R is the radius of the circular motion.
Then, for our case we have:
[tex]a_c=\frac{v_t^2}{R}=\frac{3.5^2}{0.6}\approx 20.42\,\,\frac{m}{s^2}[/tex]
And now we multiply this acceleration by Miguel's mass (11 kg) to obtain the centripetal force acting on him:
[tex]F_c=11 \,*\,20.42\,N = 224.6\,\,N[/tex]
Answer:
225 N
Explanation:
Just answered the question
(b) If you decrease the length of the pendulum by 25%, how does the new period TN compare to the old period T?
Answer:
The new period will be reduced by 50%
Explanation:
The period of pendulum is given by;
[tex]T= 2\pi\sqrt{\frac{L}{g} }\\\\\frac{T}{2\pi} = \sqrt{\frac{L}{g} }\\\\(\frac{T}{2\pi} )^2 = {\frac{L}{g}}\\\\\frac{T^2}{4\pi ^2} = {\frac{L}{g}}\\\\T^2(\frac{g}{4\pi ^2}) = L\\\\ \frac{g}{4\pi ^2}= \frac{L}{T^2}\\\\\frac{L_1}{T_1^2} = \frac{L_2}{T_2^2}[/tex]
When the length is decreased by 25%, the new length L₂ is given by;
L₂ = 25/100(L₁)
L₂ = 0.25L₁
[tex]\frac{L_1}{T_1^2} = \frac{L_2}{T_2^2}\\\\T_2^2 = \frac{T_1^2L_2}{L_1} \\\\T_N^2 = \frac{T^2(0.25L_1)}{L_1}\\\\ T_N^2 =0.25T^2\\\\T_N = \sqrt{0.25T^2}}\\\\T_N = 0.5 T[/tex]
Thus, the new period will be reduced by 50%
lol
idk what this is
Answer:
I know
Explanation:
Physics= hard
how do accelerating objects act
Explanation:
They speed up, slow down, or change direction.
Answer:In order for object to be accelerating, the net force (sum of all forces) acting on the object has to be non-zero. According to Newton's Second Law of Motion, Force = Mass x Acceleration. ... If the object is sitting motionless on the ground, then the net force (sum of all forces) acting on it is zero.
Explanation:
You are jogging with a velocity of 2 meters/second to the west, when you feel thirsty and stops to drink water after 5 seconds. First find your velocity the moment you stopped running. Then, find your acceleration during that motion. What are the units for acceleration? What is the direction of acceleration in this motion? Show your work.
Answer:
The velocity when the runner stopped is v =0 m/s
The acceleration is [tex]a = 0.4 \ m/s [/tex]
Explanation:
From the question we are told that
The initial velocity is [tex]u = 2 \ m/s[/tex]
The time taken is [tex]t = 5 \ s[/tex]
Generally from the question we are told that the person stopped running so the person velocity at that moment is v =0 m/s
Now the acceleration is mathematically represented as
[tex]a = \frac{v - u}{t}[/tex]
=> [tex]a = \frac{0 - 2}{5}[/tex]
=> [tex]a = 0.4 \ m/s [/tex]
What is the ultimate source of energy for an ecosystem?
Answer:
Obviously the answer is Sun...
What is the mass of the cube
Density is 40 g/cm3
Length of the side= 2 cm
Answer:
80
Explanation:
because of the denstiy formula
Earth's atmosphere is constantly bombarded by cosmic ray protons that originate somewhere in space. If the protons all passed through the atmosphere, each square meter of Earth's surface would intercept protons at the average rate of 1800 protons per second. What would be the electric current in amperes intercepted by a 41 × 107 km2 area on the planet
Answer:
Electric current in amperes = 1.1808 A
Explanation:
Given:
Intercept protons rate = 1800 protons per second
Area = 41 × 10⁷ km²
Find:
Electric current in amperes
Computation:
Current density = Intercept protons rate × 1.6 × 10⁻¹⁹
Current density = 1800 × 1.6 × 10⁻¹⁹
Current density = 2.88 × 10⁻¹⁶
1 km² = 10⁶m²
So,
Electric current in amperes = 2.88 × 10⁻¹⁶ × 41 × 10⁷ × 10⁶
Electric current in amperes = 1.1808 A
A cyclist accelerates from rest to 8 m/s in 3 seconds. How far did the cycles travel in 3 seconds?
Answer:
[tex] \boxed{\sf Distance \ travelled = 12 \ m} [/tex]
Given:
Initial speed (u) = 0 m/s (Accelerates from rest)
Final speed (v) = 8 m/s
Time taken (t) = 3 seconds
To Find:
Distance travelled by cyclist (s)
Explanation:
From equation of motion of object moving with uniform acceleration in straight line we have:
[tex] \boxed{ \bold{s = (\frac{v + u}{2} )t}}[/tex]
By substituting value of v, u & t in the equation we get:
[tex] \sf \implies s = ( \frac{8 + 0}{2} ) \times 3 \\ \\ \sf \implies s = \frac{8}{2} \times 3 \\ \\ \sf \implies s = 4 \times 3 \\ \\ \sf \implies s = 12 \: m[/tex]
[tex] \therefore[/tex]
Distance travelled by cyclist (s) = 12 m
Answer:
s(distance) =36m
Explanation:
u(initial velocity) =0 m/s
a =8 m/s^2
t=3s
s=ut+1/2at^2
s=1/2(8)(3)^2
s=1/2(8)(3)(3)
s=4(9)
s=36m
Air conditioners operate on the same principle as refrigerators. Consider an air conditioner that has 7.00 kg of refrigerant flowing through its circuit each cycle. The refrigerant enters the evaporator coils in phase equilibrium, with 54.0 % of its mass as liquid and the rest as vapor. It flows through the evaporator at a constant pressure and when it reaches the compressor 95% of its mass is vapor. In each cycle, how much heat Qc is absorbed by the refrigerant while it is in the evaporator? The heat of vaporization of the refrigerant is 1.50×105 J/kg
Answer:
5.15J
Explanation:
First. 54% of the 7kg refrigerant is liquid
So we find mass of vapour at inlet generator
M1 = ( 1-0.54)*7= 3.2kg
At compressor mass of vapour will be
M2= 0.95*7= 6.7kg
So the Mass of vapour at exit generator is
M2-M1= 3.5kg
So to find heat absorbed by refrigerant in evaporation
Its using
Q= mh
°= 3.5x 1.50×10^5 J/kg
=5.15J
An excited squirrel starts from rest and accelerates towards a nut at 1.0 m/s2 for 2.0 seconds. What is the squirrel’s displacement?
Answer:
[tex]x=8m[/tex]
Explanation:
Hello,
In this case, the most suitable kinematic equation for the calculation of the squirrel's displacement is:
[tex]x=v_ot+\frac{1}{2}at^2[/tex]
Whereas the initial velocity is zero as it starts from rest, thus, we obtain:
[tex]x=\frac{1}{2}*1.0\frac{m}{s^2}*(2.0s)^2\\ \\x=8m[/tex]
Best regards.
Which of the following statements about slope is NOT true?
Explanation:
did you upload a picture?
I'm confused, and I can't seem to get this question right. someone please help. Only two forces act on an object (mass = 5.00 kg), as in the drawing. (F = 55.0 N.) Find the magnitude and direction (relative to the x axis) of the acceleration of the object. (Drawing: 45 degrees, Fx is 40 N)
Answer:
17.6 m/s², 26.2° above x axis
Explanation:
Apply Newton's second law.
Sum of forces in the x direction:
∑Fₓ = ma
40 N + 55.0 N cos 45° = (5.00 kg) aₓ
aₓ = 15.8 m/s²
Sum of forces in the y direction:
∑Fᵧ = ma
55.0 N sin 45° = (5.00 kg) aᵧ
aᵧ = 7.78 m/s²
Use Pythagorean theorem to find the magnitude of the resultant.
a² = aₓ² + aᵧ²
a² = (15.8 m/s²)² + (7.78 m/s²)²
a = 17.6 m/s²
Use trigonometry to find the angle.
tan θ = aᵧ / aₓ
tan θ = (7.78 m/s²) / (15.8 m/s²)
θ = 26.2°
What was the current annual rate of inflation in 2009?
pls help !
Answer:
The 2009 inflation rate was -0.36%. The current year-over-year inflation rate (2019 to 2020) is now 0.99%
Explanation:
A highway curve with radius R = 274 m is to be banked so that a car traveling v = 25.0 m/s will not skid sideways even in the absence of friction. At what angle should the curve be banked? 2. what is the correct equation for the sum of the forces in the x direction? What is the correct equation for the sum of the forces in the y direction? A. ΣFx:−Nsinθ=mv2/R; ΣFy:Ncosθ−mg=0 B. ΣFx:−Ncosθ=−mv2/R; ΣFy:Nsinθ−mg=0 C. ΣFx:Nsinθ=mv2/R; ΣFy:Ncosθ+mg=0 D. ΣFx:−Nsinθ=mv2/R; ΣFy:Ncosθ=0 E. ΣFx:−Nsinθ=−mv2/R; ΣFy:Ncosθ−mg=0
Answer:
A) θ = 13.1º , B) E
Explanation:
A) For this exercise, let's use Newton's second law, let's set a reference frame where the axis ax is in the radial direction and is horizontal, the axis y is vertical.
In this reference system the only force that we must decompose is the Normal one, let's use trigonometry
sin θ = Nₓ / N
cos θ = [tex]N_{y}[/tex] / N
Nₓ = N sin θ
Ny = N cos θ
x-axis (radial)
Nₓ = m a
where the acceleration is centripetal
a = v² / R
we substitute
-N sin θ = -m v² / R (1)
the negative sign indicates that the force and acceleration towards the center of the circle
y-axis (Vertical)
Ny - W = 0
N cos θ = mg
N = mg / cos θ
we substitute in 1
mg / cos θ sin θ = m v² / R
g tan θ = v² / R
θ = tan⁻¹ (v² / gR)
we calculate
θ = tan⁻¹ (25² / 9.8 274)
θ = 13.1º
B) when comparing the equations the correct one is E
When a gas undergoes an isothermal process, there is
(A) no heat added to the gas.
(B) no work done by (or on) the gas.
(C) no change in the temperature of the gas.
(D) no change in the volume of the gas.
(E) no change in the pressure of the gas.
Answer:
(C) no change in the temperature of the gas.
Explanation:
isothermal process of a gas, can result to compression of the gas or expansion of the gas at a constant temperature (ΔT = 0).
For isothermal gas expansion, work is done in reducing the pressure of the gas by increasing its volume at a constant temperature. The change in the internal energy of this process is zero (ΔU = 0).
For isothermal gas compression, work is done in decreasing the volume of the gas by increasing its pressure at a constant temperature. The change in the internal energy of this process is also zero (ΔU = 0).
Therefore, when a gas undergoes an isothermal process, there is no change in the temperature of the gas.
Where do you feel that you are traveling at the fastest speed when on the swing?
Answer:
C
Explanation:
I think it's C, because at that point, you are going fastest. Sorry if im wrong, hope this helps.
Answer:
In between and the middle one
Explanation:
what role do control groups play
Answer:
Control groups let the one who is expermenting compare the effect of the varibles in the expermental group.
Explanation:
1. Looking at the planet vs. eccentricity table, which two planets have the greatest eccentricity?
Answer:
Pluto & Mercury
Explanation:
Pluto's eccentricity is 0.248
Mercury's eccentricity is 0.206