Answer:
True
Explanation:
The electromagnetic spectrum can be regarded as term that give description of range of light that are in existence, and this range from radio waves up to gamma rays. It can be explained as
range of frequencies that electromagnetic radiation takes with thier respective wavelengths as well as photon energies
The Types of electromagnetic radiation that make up the electromagnetic spectrum are
✓ microwaves
✓ infrared light
✓ ultraviolet light
✓X-rays,
✓gamma rays.
Two students engaged in a tug of war each pull a rope in opposite directions with a force of 400 N. The net force on the rope is ?
Answer:
The net force is 0.
Explanation:
If I pull to the left with 400 N and you pull to the right with 400 N, we're going in opposite directions. If the left is negative (-400N) and the right is positive (+400N), add them to get the resultant force.
PLEASE HELP ME IN THE QUESTION ALSO! because I didn't understand
Answer:
3.69 m/s²
Explanation:
weight = mass × Acceleration of gravity
479.96 = 129.72 × Acceleration of gravity
Acceleration of gravity = 479.96/129.72 = 3.69 m/s²
Calculate the standard Gibbs energy of the reaction CO(g) + CH3CH2OH(l) → CH3CH2COOH(l) at 298 K, using the values of standard entropies and enthalpies of formation. The data is given below.
CO(g) : ΔfH0 = −110.53 kJ mol-1, Sm0=197.67 J K-1 mol−1 at 298 K. CH3CH2OH(l) : ΔfH0 = −277.69 kJ mol-1, Sm0=160.7 J K-1 mol−1 at 298 K. CH3CH2COOH(l) : ΔfH0 = −510 kJ mol-1, Sm0 = 191 J K-1 mol−1 at 298 K.
Answer:
-7.2 * 10^4 kJ mol-1
Explanation:
First we obtain the change in enthalpy for the reaction;
ΔHrxn= ΔHproducts - ΔHreactants
ΔHrxn=[( −510 ) - (−110.53) + (−277.69)]
ΔHrxn= -121.78 * 3 J mol-1
The we obtain the entropy change of the reaction
ΔSrxn= ΔSproducts - ΔSreactants
ΔSrxn= [(191) - (197.67) + (160.7)]
ΔSrxn= -167.37 J K-1 mol−1
Then we calculate ΔG at 298 K
ΔG = ΔH - TΔS
ΔG = ( -121.78 * 3) - (298) (-167.37)
ΔG = -7.2 * 10^4 kJ mol-1
) If two half-open air columns A and B, that have identical lengths with one free and one fixed boundary, are subject to the same sound source frequency, what could explain why a wave may travel slower along column A compared to column B? Choose all that apply, and explain below. a) Column A has a slightly smaller diameter than column B. b) Column A is filled with argon gas, and column B is filled only with air. c) Column A and column B are identical in their fluid (i.e., air) density, except that the air in column A is at a higher temperature.
Answer:
* for the condition the velocity in column A is less than in column B
all the answers are false
* the speed of sound in column A is greater than in column B
True b and c
Explanation:
This interesting exercise we have a mixture of the resonance conditions and the conditions for the speed of sound.
The resonance condition is that at the closed end we have a node and at the open end a belly
λ = 4L first harmonic (fundamental)
The conditions of the speed of sound are
v = [tex]\sqrt{\frac{B}{ \rho } }[/tex]
the velocity for air is v = 343 m/s at 20ºC and for argon it is v = 670 m/s at 20ºC
Another relationship is that the density of a gas depends on the temperature
v = v₀ [tex]\sqrt{1 + \frac{T}{273} }[/tex]
v₀ is the speed of sound at 0ºC
let's examine the different answers
* for the condition the velocity in column A is less than in column B
a) False. The resonance does not depend on the diameter but on the length of the column
b) False. The speed of sound in argon is greater than in air, the volume modulus of argon is greater
c) False. The speed depends on the root of the temperature, increasing the temperature increases the speed of sound.
As you can see in this case all the answers are false, let's change the condition
* the speed of sound in column A is greater than in column B
a) False
b) True
c) True
explain melting and freezing using the kinetic theory of matter
As a liquid is cooled its molecules lose kinetic energy and their motion slows. When they've slowed to where intermolecular attractive forces exceed the collisional forces from random motion, then a phase transition from liquid to solid state takes place and the material freezes
Hope it helps u
FOLLOW MY ACCOUNT PLS PLS
A toroidal solenoid has a radius of 0.12 m and a cross sectional area of 20×10^-4 m2. It is found that when the current is 20A, the energy is 0.1 J. How many turns does the winding have?
Answer:
the number of turns in the winding is 387 turns.
Explanation:
Given;
radius of the solenoid, r = 0.12 m
cross sectional area of the solenoid, A = 20 x 10⁻⁴ m²
current flowing through the solenoid, I = 20 A
the energy of the flowing current, E = 0.1 J
The energy stored in solenoid is given as;
[tex]U = \frac{1}{2} LI^2\\\\L = \frac{2U}{I^2} \\\\L = \frac{2 \times 0.1}{20^2} \\\\L = 5 \times 10^{-4} \ H[/tex]
The number of turns in the winding is calculated as follows;
[tex]L = \frac{\mu_o N^2A}{2\pi r} \\\\N^2 = \frac{2\pi r L}{\mu_o A} \\\\N = \sqrt{\frac{2\pi r L}{\mu_o A}} \\\\N = \sqrt{\frac{2\pi \times 0.12 \times 5\times 10^{-4} }{4\pi \times 10^{-7} \times 20\times 10^{-4} }}\\\\N = 387 \ turns[/tex]
Therefore, the number of turns in the winding is 387 turns.
what are 3 types of contact forces
There are different types of contact forces like normal Force, spring force, applied force and tension force.
A ray of laser light strikes a glass surface at an angle a=25.0° tot he normal and it is refracted to an angle b=18.5° to the normal. What is the index of refraction nb for this type of glass? Na=1.00
A. 3.26
B. 3.52
C. 1.32
D. 1.89
Answer:
1.33
Explanation:
According to snell's law,
n = sin(a)/sin(b)
Given
a = 25.0°
b = 18.5°
Substitute
n = sin25/sin18.5
n = 0.4226/0.3173
n = 1.33
Hence the index of refraction nb for this type of glass is 1.33
When you are high up in the air you
have
greater potential energy
less potential energy
Answer:
Its Greater potential energy because the air is high up and that makes high energy power
Explanation:
What major region does this profile
most likely represent?
Given the information on the graph, we can confirm that this profile represents the Ocean floor profile.
What causes the spike in the graph?The spike in the graph demonstrates a sharp change in depth. This is caused by the irregularities we expect to find on the ocean floor. Many parts of the ocean floor are deeper than others, caused by the movement of tectonic plates over time.Therefore, we can confirm that the profile belongs to the ocean floor profile, firstly because of the information provided, as well as it being consistent with the irregularities in the depth of the ocean floor.
To learn more about the Ocean visit:
https://brainly.com/question/11803537?referrer=searchResults
A 3.00 x 10^2-W electric immersion heater is
used to heat a cup of water. The cup is made
of glass and its mass is 3.00 10^2 g. It con-
tains 250 g of water at 15° C. How much time
is needed for the heater to bring the water to
the boiling point? Assume the temperature of
the cup to be the same as the temperature of
the water at all times and no heat is lost to
the air.
Answer
t = 367.77 s = 6.13 min
Explanation:
According to the law of conservation of energy:
[tex]Heat\ Supplied\ By \ Heater = Heat\ Absorbed\ by\ Glass + Heat\ Absorbed\ by\ Water\\Pt = m_gC_g\Delta T_g + m_wC_w\Delta T_w\\[/tex]
where,
P = Electric Power of Heater = 300 W
t = time required = ?
m_g = mass of glass = 300 g = 0.3 kg
m_w = mass of water = 250 g = 0.25 kg
C_g = speicific heat of glass = 840 J/kg.°C
C_w = specific heatof water = 4184 J/kg.°C
ΔT_g = ΔT_w = Change in Temperature of Glass and water = 100°C - 15°C
ΔT_g = ΔT_w = 85°C
Therefore,
[tex](300\ W)(t) = (0.3\ kg)(840\ J/kg.^oC)(85^oC)+(0.25\ kg)(4184\ J/kg.^oC)(85^oC)\\[/tex]
t = 367.77 s = 6.13 min
The critical angle for water is 49°. If a ray of light
strikes the upper surface of a pond at an angle
of incidence of 45°, will it be totally internally
reflected? Explain your answer.
Answer:
Snell's Law states
Ni sin i = Nr sin r
Judging from the question the source of the ray is in the water (directed up)
or NI = 1 / sin 49 Ni = 1.325 deg the critical angle
From inside the pond:
Nr = 1.325 * sin 45 / 1 = 94 deg
So refraction can occur outside the pond and you do not have total internal refection.
1. Two blocks travel along a level frictionless surface. Block A is initially moving to the right at 5.0 m/s, while block B is initially at rest. After the collision, block A continues to the right at 1.0 m/s. The mass of block A is 2.0 kg and the mass of block B is 3.0 kg. The positive x-direction is to the right. a. Find the final velocity of block B. Show your work. b. Is the sign of the change in momentum of block A as a result of the collision positive, negative, or is it zero
Answer: 2.67 m/s
Explanation:
Given
Mass of block A is [tex]m_a=2\ kg[/tex]
mass of block B is [tex]m_b=3\ kg[/tex]
The initial velocity of block A [tex]u_a=5\ m/s[/tex]
the initial velocity of block B is [tex]u_b=0[/tex]
After collision velocity of block A is [tex]v_a=1\ m/s[/tex]
Conserving momentum
[tex]m_au_a+m_bu_b=m_av_a+m_bv_b\\\\2\times 5+3\times0=2\times 1+3\times v_b\\\\v_b=\dfrac{8}{3}=2.67\ m/s[/tex]
The momentum of block A after the collision is [tex]P_a=2\times 1=2\ kg.m/s[/tex]
Therefore, there is no change in sign.
2.) Assume you decided to build a cabin off the electrical grid in a remote region of the United States, and your cabin would require 720 kWh per month to easily meet your needs. You decide to produce your electricity using photovoltaic cells and store it using a battery system so that it is available when you wish to use it. If every photovoltaic cell has the potential to produce 0.25 kilowatts (250 watts), and they produced electricity for 24 hours a day, how many photovoltaic cells would you need to meet your electricity needs for a month
Answer:
4 photovoltaic cells are required to meet monthly energy consumption of the cabin.
Explanation:
Let suppose that PV generation system produces energy at constant energy, the number of photovoltaic system to meet energy consumption of the cabin is:
[tex]n = \frac{E}{\dot E \cdot t}[/tex] (1)
Where:
[tex]E[/tex] - Energy consumption of the PV system, in kilowatt-hours.
[tex]\dot E[/tex] - Power generation of the PV cell, in kilowatts.
[tex]t[/tex] - Working times, in hours.
If we know that [tex]E = 720\,kWh[/tex], [tex]\dot E = 0.25\,kW[/tex] and [tex]t = 720\,h[/tex], then the number of photovoltai cells is:
[tex]n = \frac{E}{\dot E \cdot t}[/tex]
[tex]n = 4[/tex]
4 photovoltaic cells are required to meet monthly energy consumption of the cabin.
Recall your experimental setup from Lab 05A: a constant force was applied to a disc by attaching a mass to a light string wrapped around a mass-less pulley and hanging the mass over the edge of the apparatus. In the lab, you used energy conservation arguments to derive an expression for the angular velocity of the disc after the mass had fallen a distance x . Your goal now is to use kinematics and dynamics to confirm your expression. Use the following symbols throughout this question: m is the mass of the hanging mass, M is the mass of the disc, r is the radius of the pulley, R is the radius of the disc, x is the distance the mass has fallen, and g is the acceleration due to gravity. What is the linear acceleration of the mass after it has fallen a distance x
Answer:
w = [tex]\sqrt{\frac{2gy}{r^2 + \frac{1}{2} R^2 } }[/tex]
Explanation:
For this exercise let's start by applying Newton's second law to the mass with the string
W - T = m a
In this case, as the system is going down, we will assume the vertical directional down as positive.
T = W - m a
Now we apply Newton's second law for rotational motion to the pulley of radius r. We will assume the positive counterclockwise rotations
∑ τ = I α
T r = I α
the moment of inertia of the disk is
I = ½ M R²
angular and linear acceleration are related
a = α r
we substitute
T r = (½ m R²) (a / r)
T = ½ m ([tex]\frac{R}{r}[/tex] )² a
we write our two equations
T = W - m a
T = ½ m ([tex]\frac{R}{r}[/tex] )² a
we solve the system of equations
W - m a = ½ m (\frac{R}{r} )² a
m g = m a [ 1 + ½ (\frac{R}{r} )² ]
a = [tex]\frac{g}{ 1 + \frac{1}{2} (\frac{R}{r})^2 }[/tex]
this acceleration is constant throughout the trajectory, so with the angular and lineal kinematics relations
w² = w₀² + 2 α θ
v² = v₀² + 2 a y
as the system is released its initial angular velocity is zero
w² = 0 + 2 α θ
v² = 0 + 2 a y
we look for the angular acceleration
a =α r
α = a / r
α = [tex]\frac{g}{r (1 + \frac{1}{2} (\frac{R}{r})^2 }[/tex]
we look for the angle, remember that they must be measured in radians
θ = s / r
in this case we approximate the arc to the distance
s = y
θ = y / r
we substitute
w = [tex]\sqrt{2 \frac{g}{ r( \frac{1}{2} (\frac{R}{r})^2 } \frac{y}{r} }[/tex]
w = [tex]\sqrt{\frac{2gy}{r^2 + \frac{1}{2} R^2 } }[/tex]
for the simple case where r = R
w = [tex]\sqrt{ \frac{2gy}{ \frac{3}{2} R^2 } }[/tex]
w = [tex]\sqrt{ \frac{4}{3} \frac{gy}{R^2} }[/tex]
Which of the following is not true of a topic sentence?
A It should support or reinforce the thesis statement in some way.
B. Every body paragraph should have one.
C. It should summarize the main idea of the paragraph.
O D. It should summarize the main idea of the essay.
Answer: its d
Explanation:
which letter represents the way the wave is moving?
Wouldn't it be B because it's a majority pointing to it?
Sorry if i'm wrong.
The brightness of a star depends on what
two things?
A. age and color
B. temperature and age
C. size and age
D. size and temperature
Please help The half-life of argon-44 is 12 minutes. Suppose you start with 20 atoms of
argon-44 and wait 12 minutes. How many atoms of argon-44 will be left?
A. 20 atoms
B. 40 atoms
C. 5 atoms
D. 10 atoms
Answer:
D. 10 atoms
Explanation:
Franny drew a diagram to compare images produced by concave and convex lenses.
2 overlapping circles, the left circle labeled Concave lenses and the right circle labeled Convex lenses. An X in the overlap.
Which belongs in the area marked X?
Answer:
Virtual
Explanation:
Answer:
B. Virtual
Good Luck!
Mosses don't spread by dispersing seeds; they disperse tiny spores. The spores are so small that they will stay aloft and move with the wind, but getting them to be windborne requires the moss to shoot the spores upward. Some species do this by using a spore-containing capsule that dries out and shrinks. The pressure of the air trapped inside the capsule increases. At a certain point, the capsule pops, and a stream of spores is ejected upward at 3.6 m/sm/s, reaching an ultimate height of 20 cm.
Required:
What fraction of the initial kinetic energy is converted to the final potential energy?
Answer:
U / K = 0.30
Explanation:
For this exercise we must calculate the energy at the two points.
Initial. Where are the spores
K = ½ m v²2
Final. Higher
U = m g h
the fraction of energy is
U / K = 2gh /v²
let's calculate
U / K = 2 9.8 0.20 / 3.6²
U / K = 0.30
therefore 30% of the energy is lost
A student flexes her neck to 40 degrees from vertical while studying for her final exam. She pivots her head around the upper vertebra, approximated as point P (in the middle of the picture). Her head has a mass of 4.5 kg, and its center of mass is 11 cm away from point P. Her neck muscles are 1.5 cm from point P, measured perpendicular and pulling straight down. How much force do the neck muscles have to exert to keep the head still
Answer:
[tex]T=208N[/tex]
Explanation:
From the question we are told that:
Neck flex angle [tex]\angle_n=40 \textdegree[/tex]
Head mass [tex]M_h=4.5kg[/tex]
Center of mass [tex]M_c= 11cm[/tex]
Distance of neck from P [tex]d_p=1.5cm[/tex]
Let
[tex]T_g=Gravitational\ force\ torque\\T_{nm}=Tension\ on\ neck\ muscle\ torque[/tex]
Generally the net Torque T_n is mathematically given by
[tex]T_n=0[/tex]
Therefore
[tex]T_g-T_{nm}=0[/tex]
Generally the equation for Torque T is mathematically given by
[tex]T=\frac{M_h*g*l_g}{d_p}[/tex]
where
[tex]l_g=M_c*sin\angle_n[/tex]
[tex]l_g=11*10^{-2}*sin40[/tex]
[tex]l_g=0.07m[/tex]
Therefore
[tex]T=\frac{4.5*9.8*0.07}{1.5*10^{-2}}[/tex]
[tex]T=208N[/tex]
Which object will have the most kinetic energy?
a 0.045 kg golf ball traveling at 41 m/s
a 0.057 kg tennis ball traveling at 20 m/s
a 0.14 kg baseball traveling at 40 m/s
a 5 kg bowling ball traveling at 3 m/s
Answer:
c baseball
Explanation:
the baseball traveling at 40m/seg
In this equation, what shows that transmutation has taken place?
242. 238. 4
96Cm →94 Pu +2 He
A. There is conservation of both nucleons and atoms.
B. The nucleus of an atom changes.
C. The number of atoms is conserved, but the number of nucleons is
not.
D. It involves more than one element.
Answer:
The Nucleus of an atom change
Explanation:
Ap3x
A hammer strikes one end of a thick iron rail of length 8.80 m. A microphone located at the opposite end of the rail detects two pulses of sound, one that travels through the air and a longitudinal wave that travels through the rail. (The speeds of sound in air and in iron are 343 m/s and 5950 m/s, respectively.)
Required:
Find the separation in time between the arrivals of the two pulses.
Answer:
ΔT = 0.02412 s
Explanation:
We will simply calculate the time for both the waves to travel through rail distance.
FOR THE TRAVELING THROUGH RAIL:
[tex]T_{rail} = \frac{Distance}{Speed\ of\ Sound\ in\ Rail}\\\\T_{rail} = \frac{8.8\ m}{5950\ m/s}\\\\T_{rail} = 0.00148\ s[/tex]
FOR THE WAVE TRAVELING THROUGH AIR:
[tex]T_{air} = \frac{Distance}{Speed\ of\ Sound\ in\ Air}\\\\T_{air} = \frac{8.8\ m}{343\ m/s}\\\\T_{air} = 0.0256\ s[/tex]
The separation in time between two pulses can now be given as follows:
[tex]\Delta T = T_{air}-T_{rail} \\\Delta T = 0.0256\ s - 0.00148\ s\\[/tex]
ΔT = 0.02412 s
The frequency, or pitch, of a musical note varies inversely with
the wavelength. The speed of sound, 340.2 meters per second, is
the constant of variation.
An "A" note in octave 3, has a frequency of 220 Hertz. What is the
wavelength of the sound made by the tuner in meters?
Answer:
0.647 meters
Explanation:
i did the quiz
: Suppose somebody, using the same apparatus which you used, measured I = 45.5 ma, and V = 8.2 volts on some resistor. Using your recorded uncertainties for the 50 ma and 10-volt scales, what would be the maximum % uncertainty in R if it were calculated from the Ohm’s Law Equation (1)? Use calculus methods to answer this question if you can.
Answer:
R = (18 ± 2) 10¹ Ω
ΔR = 2 10¹ Ω
Explanation:
Ohm's law relates voltage to current and resistance
V = i R
R = [tex]\frac{V}{i}[/tex]V / i
the absolute error of the resistance is
ΔR = | [tex]| \frac{dR}{DV} | \ \Delta V + | \frac{dR}{di} | \ \Delta i[/tex]
the absolute value guarantees the worst case, maximum error
ΔR = [tex]\frac{1}{i} \Delta V+ \frac{V}{i^2} \Delta i[/tex]
The error in the voltage let be approximate, if we use a scale of 10 V, in general the scales are divided into 20 divisions, the error is the reading of 1 division, let's use a rule of direct proportion
ΔV = 1 division = 10 V / 20 divisions
ΔV = 0.5 V
The current error must also be approximate, if we have the same number of divisions
Δi = 50 mA / 20 divisions
Δi = 2.5 mA
let's calculate
ΔR = [tex]\frac{1}{45.5 \ 10^{-3}} \ 0.5 + \frac{8.2}{(45.5 \ 10^{-3})^2 } \ 2.5 \ 10^{-3}[/tex]
ΔR = 10.99 + 9.9
ΔR = 20.9 Ω
The absolute error must be given with a significant figure
ΔR = 2 10¹ Ω
the resistance value is
R = 8.2 / 45.5 10-3
R = 180 Ω
the result should be
R = (18 ± 2) 10¹ Ω
can u pls help me ........
Answer:
solidification
Explanation:
a liquid becoming a solid, is called solidification. For any pure substance, the temperature at which melting occurs—known as the melting point—is a characteristic of that substance.
Light from the Sun is converted into
.... by plants.
Answer:
Explanation:
The answer is chemical energy
Weather is caused by the rising and falling of warm and cool air called
Answer:
Convection currents
Explanation:
As hot air cools it sinks back to the surface of the earth, where it gets warmed by the ocean only to rise again. This is called a convection current. Convection currents are defined as room air rising and cold air sinking
~Hope this helps
~Bre