Tüm alıştırma soruları

13931 soru

Soru 7181Soru

An optical communication sensor operates using an electromagnetic wave with a frequency of 1.5×1014 Hz1.5 \times 10^{14}\text{ Hz} in a vacuum. Given that the speed of light in vacuum is 3.0×108 m/s3.0 \times 10^8\text{ m/s}, what is the wavelength of this electromagnetic radiation?

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Cevap: 2.0×106 m2.0 \times 10^{-6}\text{ m}

Cevap

The wavelength of the electromagnetic wave is 2.0×106 m2.0 \times 10^{-6}\text{ m}.
Using the electromagnetic wave relation c=fλc = f\lambda, dividing the speed of light (3.0×108 m/s3.0 \times 10^8\text{ m/s}) by the given frequency (1.5×1014 Hz1.5 \times 10^{14}\text{ Hz}) correctly gives 2.0×106 m2.0 \times 10^{-6}\text{ m}.

Adım Adım Çözüm

1
Identify given quantities and formula
Speed of light c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s}, frequency f=1.5×1014 Hzf = 1.5 \times 10^{14}\text{ Hz}, wave equation c=fλc = f \lambda
The fundamental wave equation relates wave speed, frequency, and wavelength for all electromagnetic waves.
2
Rearrange formula to solve for wavelength λ\lambda
\(\lambda = \frac{c}{f}\)
Isolating the target unknown variable allows direct calculation.
3
Substitute values and compute
\(\lambda = \frac{3.0 \times 10^8}{1.5 \times 10^{14}} = 2.0 \times 10^{-6}\text{ m}\)
Dividing the coefficients (3.0/1.5=2.03.0 / 1.5 = 2.0) and subtracting the powers of ten (814=68 - 14 = -6) yields the accurate wavelength.

Anahtar Kavram

Wave Equation for Electromagnetic Waves
Soru 7182Soru

What is the bond angle between adjacent single covalent bonds formed by a tetrahedral sp3sp^3 hybridized carbon atom in a saturated organic compound?

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Cevap: 109.5109.5^\circ

Cevap

The bond angle of a tetrahedral sp³ hybridized carbon atom is 109.5°.
In saturated organic compounds such as alkanes, the central carbon atom forms four single sigma bonds using four equivalent sp3sp^3 hybrid orbitals. According to VSEPR theory, four bonding electron pairs surrounding a central atom arrange themselves in a regular tetrahedral shape to minimize electrostatic repulsion, yielding a standard bond angle of 109.5109.5^\circ.

Adım Adım Çözüm

1
Determine the hybridization state of a carbon atom forming four single sigma bonds.
Mixing one 2s orbital and three 2p orbitals gives four equivalent sp3sp^3 hybrid orbitals.
Saturated carbon forms four single bonds by directed valence orbital mixing.
2
Apply VSEPR theory to determine spatial orientation for four electron pairs around the central carbon.
To minimize electron pair repulsion, the four orbitals point toward the vertices of a regular tetrahedron.
Symmetrical four-coordinate electron pair repulsion produces tetrahedral spatial orientation.
3
Identify the characteristic inter-bond angle of a regular tetrahedron.
The angle between any two adjacent bonds is 109.5109.5^\circ (or 10928109^\circ 28').
This angle maximizes the distance between the four bonding electron pairs in three-dimensional space.

Anahtar Kavram

Tetrahedral Geometry and sp³ Hybridization Bond Angle
Tahmini Süre:45s
Soru 7183Soru

A pure chemical compound analyzed using thin-layer or paper chromatography under standard conditions produces a single distinct spot on the developed chromatogram.

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Cevap: True

Cevap

The statement is true because pure substances contain only one component and yield a single spot during chromatographic separation.
A fundamental criterion of chemical purity is that a pure substance gives a single spot on a chromatogram, as it contains no additional chemical species to separate out.

Adım Adım Çözüm

1
Identify the core principle of chromatography as a test of purity.
Chromatography separates components of a sample based on their relative affinities for the stationary and mobile phases.
Understanding how chromatography separates substances helps evaluate purity criteria.
2
Relate component count to the number of spots observed.
A pure compound contains only one chemical species, so it does not separate into multiple components and produces a single spot.
The appearance of more than one spot signifies a mixture containing impurities.

Anahtar Kavram

Single spot on a chromatogram as a criterion of chemical purity
Soru 7184Soru

Arrange the following types of electromagnetic radiation in order of increasing frequency (from lowest frequency to highest frequency).

Öğeleri doğru sıraya koymak için sürükleyin

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Cevap

The correct sequence of electromagnetic radiations in order of increasing frequency is: Microwaves, Infrared radiation, Ultraviolet radiation, and Gamma rays.
Electromagnetic waves propagate at the constant speed c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s} in a vacuum. Frequency increases as wavelength decreases across the spectrum. Microwaves have the longest wavelength and lowest frequency among the choices, followed by infrared radiation, ultraviolet radiation, and finally gamma rays, which possess the shortest wavelength and highest frequency.

Adım Adım Çözüm

1
Recall the arrangement of the electromagnetic spectrum in terms of frequency and wavelength.
In the electromagnetic spectrum, frequency increases in the order: Radio waves \rightarrow Microwaves \rightarrow Infrared \rightarrow Visible light \rightarrow Ultraviolet \rightarrow X-rays \rightarrow Gamma rays.
Electromagnetic wave energy E=hfE = hf and frequency f=cλf = \frac{c}{\lambda} increase as wavelength decreases.
2
Identify the relative position of each given radiation type along the frequency scale.
Microwaves (1091011 Hz10^9 - 10^{11}\text{ Hz}) < Infrared (10111014 Hz10^{11} - 10^{14}\text{ Hz}) < Ultraviolet (10151016 Hz10^{15} - 10^{16}\text{ Hz}) < Gamma rays (>1019 Hz>10^{19}\text{ Hz}).
Comparing their characteristic frequency ranges determines their exact position in the sequence.
3
Order the items from lowest to highest frequency.
1st: Microwaves, 2nd: Infrared radiation, 3rd: Ultraviolet radiation, 4th: Gamma rays.
This sequence satisfies the requirement of strictly increasing frequency.

Anahtar Kavram

Electromagnetic Spectrum Ordering by Frequency and Wavelength
Soru 7185Soru

A particle undergoing simple harmonic motion moves with an angular frequency of 4 rad/s4\text{ rad/s} and an amplitude of 0.5 m0.5\text{ m}. What is the maximum speed of the particle in m/s\text{m/s}?

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Cevap: 2

Cevap

The maximum speed of the particle is 2.0 m/s2.0\text{ m/s}.
The magnitude of velocity in simple harmonic motion varies with displacement xx according to v=ωA2x2v = \omega \sqrt{A^2 - x^2}. The speed reaches its maximum value when the particle passes through the equilibrium position (x=0x = 0), giving vmax=ωAv_{\text{max}} = \omega A. Substituting ω=4 rad/s\omega = 4\text{ rad/s} and A=0.5 mA = 0.5\text{ m} gives vmax=4×0.5=2.0 m/sv_{\text{max}} = 4 \times 0.5 = 2.0\text{ m/s}.

Adım Adım Çözüm

1
Identify the given physical parameters.
ω=4 rad/s\omega = 4\text{ rad/s} and A=0.5 mA = 0.5\text{ m}
These values define the speed profile of the simple harmonic oscillator.
2
Apply the SHM formula for maximum speed.
vmax=ωAv_{\text{max}} = \omega A
Peak speed occurs at the equilibrium position where displacement is zero.
3
Substitute the values to calculate the maximum speed.
vmax=4×0.5=2.0 m/sv_{\text{max}} = 4 \times 0.5 = 2.0\text{ m/s}
Multiplying angular frequency by amplitude yields the maximum linear velocity.

Anahtar Kavram

Maximum speed in Simple Harmonic Motion
Soru 7186Soru

If the matrix A=(1022k1314)A = \begin{pmatrix} 1 & 0 & 2 \\ 2 & k & 1 \\ 3 & 1 & 4 \end{pmatrix} is singular, what is the value of kk?

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Cevap: 32\frac{3}{2}

Cevap

32\frac{3}{2}
A matrix is singular if its determinant equals zero. Expanding the determinant of matrix AA along its first row gives 1(4k1)0+2(23k)=2k+31(4k - 1) - 0 + 2(2 - 3k) = -2k + 3. Setting 2k+3=0-2k + 3 = 0 yields k=32k = \frac{3}{2}.

Adım Adım Çözüm

1
Apply the condition for a singular matrix
A matrix is singular when its determinant equals zero, so det(A)=0\det(A) = 0.
By definition, square matrices with zero determinant are singular.
2
Expand det(A)\det(A) along the first row
det(A)=1(4k1)0(83)+2(23k)=4k1+46k=2k+3\det(A) = 1(4k - 1) - 0(8 - 3) + 2(2 - 3k) = 4k - 1 + 4 - 6k = -2k + 3.
Laplace expansion along the first row simplifies computation due to the zero entry.
3
Solve for kk
2k+3=0    2k=3    k=32-2k + 3 = 0 \implies 2k = 3 \implies k = \frac{3}{2}.
Isolating the variable gives the required value of kk.

Anahtar Kavram

Singular Matrix Condition and 3x3 Determinant Expansion
Soru 7187Soru

Which of the following physical properties best confirms that a solid chemical sample is pure?

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Cevap: It melts completely at a sharp, fixed temperature.

Cevap

It melts completely at a sharp, fixed temperature.
Pure solid compounds melt at a fixed, sharp temperature characteristic of that substance. A sharp melting point is a definitive physical criterion of purity for crystalline solids.

Adım Adım Çözüm

1
Identify the standard criteria of purity for a solid substance.
A pure solid possesses a sharp and definite melting point.
Soluble impurities disrupt the uniform crystal lattice of a solid, depressing its melting point and causing it to melt over a broad temperature range.

Anahtar Kavram

Criteria of purity for solid substances
Soru 7188Soru

A series alternating current circuit comprises a resistor with resistance 30 Ω30\ \Omega, an inductor with inductive reactance 80 Ω80\ \Omega, and a capacitor with capacitive reactance 40 Ω40\ \Omega. What is the total impedance of the circuit?

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Cevap: 50 Ω50\ \Omega

Cevap

The impedance of the circuit is 50 Ω50\ \Omega.
The impedance ZZ of a series RLC circuit is calculated using the formula Z=R2+(XLXC)2Z = \sqrt{R^2 + (X_L - X_C)^2}. Substituting the given values R=30 ΩR = 30\ \Omega, XL=80 ΩX_L = 80\ \Omega, and XC=40 ΩX_C = 40\ \Omega yields Z=302+(8040)2=900+1600=50 ΩZ = \sqrt{30^2 + (80 - 40)^2} = \sqrt{900 + 1600} = 50\ \Omega.

Adım Adım Çözüm

1
Calculate the net reactance (XnetX_{net})
Xnet=XLXC=80 Ω40 Ω=40 ΩX_{net} = X_L - X_C = 80\ \Omega - 40\ \Omega = 40\ \Omega
Inductive and capacitive reactances are 180180^\circ out of phase in a series AC circuit.
2
Apply the series impedance formula
Z=R2+Xnet2=302+402=900+1600=2500=50 ΩZ = \sqrt{R^2 + X_{net}^2} = \sqrt{30^2 + 40^2} = \sqrt{900 + 1600} = \sqrt{2500} = 50\ \Omega
Resistance and net reactance act at 9090^\circ phase to each other, requiring the Pythagorean relation.

Anahtar Kavram

Impedance of a Series RLC Circuit
Soru 7189Soru

Match each redox description on the left with its corresponding classical or modern definition concept on the right.

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Öğeler

Addition of oxygen to a substance
Loss of electrons by a chemical species
Decrease in the oxidation state of an element
Removal of oxygen from a compound

Eşleşmeler

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Cevap

Addition of oxygen matches Classical oxidation; Loss of electrons matches Modern oxidation (electron transfer); Decrease in oxidation state matches Modern reduction (oxidation state change); Removal of oxygen matches Classical reduction.
Classical oxidation involves gaining oxygen, while classical reduction involves losing oxygen. In modern electronic terms, oxidation is the loss of electrons (OIL), and reduction is a decrease in oxidation state (reduction of oxidation number).

Adım Adım Çözüm

1
Identify classical redox concepts based on oxygen transfer.
Addition of oxygen corresponds to classical oxidation, whereas removal of oxygen corresponds to classical reduction.
Classical definitions focused on the transfer of oxygen and hydrogen atoms.
2
Identify modern redox concepts based on electron transfer and oxidation numbers.
Loss of electrons corresponds to modern oxidation, and a decrease in oxidation state corresponds to modern reduction.
Modern concepts expand redox beyond oxygen/hydrogen to include electron movement and formal charge changes.

Anahtar Kavram

Distinguishing between classical (oxygen/hydrogen transfer) and modern (electron transfer and oxidation number) definitions of oxidation and reduction.
Tahmini Süre:1m 0s
Soru 7190Soru

A diver is swimming at a depth of 3.5 m3.5\text{ m} below the surface of a freshwater lake. If the density of water is 1000 kg/m31000\text{ kg/m}^3 and the acceleration due to gravity g=10 m/s2g = 10\text{ m/s}^2, what is the gauge pressure exerted on the diver in pascals?

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Cevap: 35000

Cevap

35000 Pa
The gauge pressure exerted by a static column of fluid is given by P=hρgP = h \rho g. Using the values h=3.5 mh = 3.5\text{ m}, ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2, the pressure is P=3.5×1000×10=35000 PaP = 3.5 \times 1000 \times 10 = 35000\text{ Pa}.

Adım Adım Çözüm

1
Identify the formula for liquid hydrostatic pressure
P=hρgP = h \rho g
Gauge pressure at a depth hh in a static fluid depends on depth, fluid density, and gravitational field strength.
2
Substitute the given numerical values
P=3.5×1000×10P = 3.5 \times 1000 \times 10
Substitute depth h=3.5 mh = 3.5\text{ m}, density ρ=1000 kg/m3\rho = 1000\text{ kg/m}^3, and g=10 m/s2g = 10\text{ m/s}^2.
3
Perform the multiplication to determine the pressure
35000 Pa35000\text{ Pa}
Complete the calculation to get the pressure in SI units (Pascals).

Anahtar Kavram

Hydrostatic Pressure in Static Fluids
Tahmini Süre:45s
Soru 7191Soru

A capacitor of capacitance 50 μF50\ \mu\text{F} is connected across an alternating current (AC) source operating at a frequency of 100π Hz\frac{100}{\pi}\ \text{Hz}. What is the capacitive reactance of the capacitor?

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Cevap: 100

Cevap

The capacitive reactance of the capacitor is 100 Ω100\ \Omega.
Capacitive reactance XCX_C is given by the formula XC=12πfCX_C = \frac{1}{2\pi f C}. Substituting C=50×106 FC = 50 \times 10^{-6}\ \text{F} and f=100π Hzf = \frac{100}{\pi}\ \text{Hz} into the formula yields XC=12π(100/π)(50×106)=1102=100 ΩX_C = \frac{1}{2\pi (100/\pi) (50 \times 10^{-6})} = \frac{1}{10^{-2}} = 100\ \Omega.

Adım Adım Çözüm

1
Convert capacitance to farads and state all given values
C=50×106 FC = 50 \times 10^{-6}\ \text{F} and f=100π Hzf = \frac{100}{\pi}\ \text{Hz}
Calculations require standard SI base units.
2
Apply the formula for capacitive reactance
XC=12πfCX_C = \frac{1}{2\pi f C}
Capacitive reactance measures the opposition offered by a capacitor to alternating current.
3
Substitute the values and calculate the result
XC=12π100π(50×106)=110,000×106=100 ΩX_C = \frac{1}{2\pi \cdot \frac{100}{\pi} \cdot (50 \times 10^{-6})} = \frac{1}{10,000 \times 10^{-6}} = 100\ \Omega
The factor π\pi cancels out directly, making the arithmetic simple.

Anahtar Kavram

Capacitive Reactance in AC Circuits
Soru 7192Soru

A solid uniform cylinder of height 0.20 m0.20\text{ m} and cross-sectional area 5.0×103 m25.0 \times 10^{-3}\text{ m}^2 floats vertically at the boundary between oil of density 800 kg/m3800\text{ kg/m}^3 and water of density 1000 kg/m31000\text{ kg/m}^3. If a height of 0.08 m0.08\text{ m} of the cylinder extends into the water layer while the remaining upper portion is completely covered by the oil layer, what is the mass of the cylinder in kilograms?

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Cevap: 0.88

Cevap

The mass of the cylinder is 0.88 kg0.88\text{ kg}.
According to the Law of Flotation, a floating body displaces its own weight of fluid. When floating at the interface of two immiscible liquids, the total mass of the body equals the sum of the masses of the displaced liquids. Displaced water mass is ρwAhw=0.40 kg\rho_w A h_w = 0.40\text{ kg} and displaced oil mass is ρoAho=0.48 kg\rho_o A h_o = 0.48\text{ kg}, giving a total cylinder mass of 0.88 kg0.88\text{ kg}.

Adım Adım Çözüm

1
Find the height of the cylinder submerged in the oil layer.
ho=0.20 m0.08 m=0.12 mh_o = 0.20\text{ m} - 0.08\text{ m} = 0.12\text{ m}
The total cylinder height is 0.20 m0.20\text{ m}, and 0.08 m0.08\text{ m} is submerged in water.
2
Calculate the volumes of water and oil displaced by the cylinder.
Vw=5.0×103×0.08=4.0×104 m3V_w = 5.0 \times 10^{-3} \times 0.08 = 4.0 \times 10^{-4}\text{ m}^3; Vo=5.0×103×0.12=6.0×104 m3V_o = 5.0 \times 10^{-3} \times 0.12 = 6.0 \times 10^{-4}\text{ m}^3
Volume displaced in each fluid equals cross-sectional area multiplied by the submerged height in that fluid.
3
Calculate the mass of the floating cylinder using the Law of Flotation.
m=ρwVw+ρoVo=(1000×4.0×104)+(800×6.0×104)=0.40 kg+0.48 kg=0.88 kgm = \rho_w V_w + \rho_o V_o = (1000 \times 4.0 \times 10^{-4}) + (800 \times 6.0 \times 10^{-4}) = 0.40\text{ kg} + 0.48\text{ kg} = 0.88\text{ kg}
For a floating object in static equilibrium, its mass equals the total mass of the fluids displaced by its submerged parts.

Anahtar Kavram

Law of Flotation in Layered Liquids
Tahmini Süre:1m 30s
Soru 7193Soru

A tripositive ion, X3+X^{3+}, has a mass number of 5656 and contains 2323 electrons. How many neutrons are present in the nucleus of an atom of element XX?

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Cevap: 30

Cevap

30
To find the number of neutrons, first determine the atomic number (number of protons) of element XX. The ion X3+X^{3+} carries a +3+3 charge because it lost 3 electrons. Since X3+X^{3+} has 23 electrons, the neutral atom XX has 23+3=2623 + 3 = 26 electrons, which means it has 26 protons. The mass number (A=56A = 56) is the sum of protons (ZZ) and neutrons (NN). Thus, N=5626=30N = 56 - 26 = 30.

Adım Adım Çözüm

1
Determine the atomic number (number of protons) of element XX
Protons (ZZ) = 26
The tripositive ion X3+X^{3+} has lost 3 electrons. The neutral atom has 23+3=2623 + 3 = 26 electrons, which equals its proton count.
2
Calculate the number of neutrons
Neutrons (NN) = 30
Subtract the atomic number from the mass number: N=AZ=5626=30N = A - Z = 56 - 26 = 30.

Anahtar Kavram

Calculation of subatomic particles in ions using atomic number and mass number relationships
Soru 7194Soru

According to the kinetic molecular theory, collisions between gas particles and the walls of their container are completely inelastic, resulting in a continuous loss of kinetic energy.

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Cevap: False

Cevap

The statement is False. Collisions of gas particles with container walls are assumed to be perfectly elastic, meaning no kinetic energy is lost.
The statement is incorrect because kinetic molecular theory assumes perfectly elastic collisions, preserving total kinetic energy and sustaining constant pressure.

Adım Adım Çözüm

1
Identify the kinetic molecular theory postulate concerning molecular collisions.
The kinetic molecular theory specifies that all collisions between gas molecules or between molecules and the container walls are perfectly elastic.
Elasticity ensures that the average kinetic energy of the gas remains constant at a given temperature.
2
Compare the statement with the established postulate.
The statement claims collisions are 'completely inelastic' with a 'continuous loss of kinetic energy', which directly contradicts the elastic collision postulate.
An inelastic collision process would violate energy conservation for ideal gas systems at thermal equilibrium.

Anahtar Kavram

Elasticity of Collisions in Kinetic Molecular Theory
Soru 7195Soru

The saturated vapour pressure of water at the dew point of a mass of air is 12 mmHg12\text{ mmHg}, while the saturated vapour pressure at the actual air temperature is 24 mmHg24\text{ mmHg}. Calculate the relative humidity of the air.

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Cevap: 50

Cevap

The relative humidity of the air is 50%.
Relative humidity is the ratio of the saturated vapour pressure at the dew point to the saturated vapour pressure at the actual air temperature, expressed as a percentage: (12 mmHg / 24 mmHg) * 100% = 50%.

Adım Adım Çözüm

1
Identify the saturated vapour pressure at the dew point and at the air temperature.
SVP at dew point = 12 mmHg; SVP at air temperature = 24 mmHg.
Relative humidity relies on the ratio of partial vapour pressure (SVP at dew point) to maximum vapour pressure at air temperature.
2
Apply the relative humidity formula.
Relative Humidity = (SVP at dew point / SVP at air temperature) * 100%
This formula defines the percentage saturation of the air.
3
Substitute the values and evaluate.
(12 / 24) * 100% = 50%
Dividing 12 by 24 gives 0.5, which equals 50% when multiplied by 100.

Anahtar Kavram

Relative Humidity Calculation
Tahmini Süre:45s
Soru 7196Soru

An FM radio station transmits electromagnetic waves at a frequency of 1.0×108 Hz1.0 \times 10^8\text{ Hz} in a vacuum. Given that the speed of light in a vacuum is 3.0×108 m/s3.0 \times 10^8\text{ m/s}, what is the wavelength of these radio waves in meters?

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Cevap: 3

Cevap

The wavelength of the radio waves is 3.0 m3.0\text{ m}.
Applying the wave equation c=fλc = f\lambda, rearranging to λ=cf\lambda = \frac{c}{f}, and substituting c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s} and f=1.0×108 Hzf = 1.0 \times 10^8\text{ Hz} gives a wavelength of 3.0 m3.0\text{ m}.

Adım Adım Çözüm

1
Identify given parameters and key formula
Speed of light c=3.0×108 m/sc = 3.0 \times 10^8\text{ m/s}, frequency f=1.0×108 Hzf = 1.0 \times 10^8\text{ Hz}, wave equation c=fλc = f\lambda
The electromagnetic wave equation relates speed, frequency, and wavelength.
2
Rearrange for wavelength and substitute given values
\lambda = \frac{c}{f} = \frac{3.0 \times 10^8}{1.0 \times 10^8} = 3.0\text{ m}
Dividing the speed of propagation by the wave frequency yields the spatial wavelength.

Anahtar Kavram

Wave equation relating speed, frequency, and wavelength of electromagnetic waves
Soru 7197Soru

The line y=2x1y = 2x - 1 intersects the curve y=x24x+4y = x^2 - 4x + 4 at two distinct points, (x1,y1)(x_1, y_1) and (x2,y2)(x_2, y_2). Calculate the sum of the yy-coordinates of these two points of intersection, y1+y2y_1 + y_2.

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Cevap: 10

Cevap

The sum of the yy-coordinates of the points of intersection is 10.
Equating y=2x1y = 2x - 1 and y=x24x+4y = x^2 - 4x + 4 yields x26x+5=0x^2 - 6x + 5 = 0, whose solutions are x=1x = 1 and x=5x = 5. Substituting these values into y=2x1y = 2x - 1 gives y1=1y_1 = 1 and y2=9y_2 = 9. The sum y1+y2=1+9=10y_1 + y_2 = 1 + 9 = 10.

Adım Adım Çözüm

1
Equate the linear and quadratic equations to eliminate yy.
x26x+5=0x^2 - 6x + 5 = 0
Setting 2x1=x24x+42x - 1 = x^2 - 4x + 4 allows finding the xx-coordinates of the intersection points.
2
Solve the quadratic equation for xx.
x1=1x_1 = 1 and x2=5x_2 = 5
Factoring (x1)(x5)=0(x - 1)(x - 5) = 0 yields the two xx-values.
3
Determine the corresponding yy-values using y=2x1y = 2x - 1.
y1=1y_1 = 1 and y2=9y_2 = 9
Substituting x=1x = 1 yields y=1y = 1, and substituting x=5x = 5 yields y=9y = 9.
4
Calculate the sum of the yy-coordinates.
10
Adding y1+y2=1+9=10y_1 + y_2 = 1 + 9 = 10.

Anahtar Kavram

Solving simultaneous linear and quadratic equations to find coordinates of intersection
Soru 7198Soru

Match each feature observed during electrical discharge through a gas with its corresponding pressure stage or physical characteristic.

Soldaki öğeye tıklayın, sonra eşleşen sağdaki öğeye tıklayın

Öğeler

Cathode Glow
Striations
Crookes Dark Space

Eşleşmeler

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Cevap

Cathode Glow matches 'Luminous glow appearing right next to the cathode at around 10 mmHg pressure', Striations match 'Alternating bright and dark bands in the positive column at around 1 mmHg pressure', and Crookes Dark Space matches 'Dark region extending to fill most of the tube at very low pressure around 0.01 mmHg'.
Each feature of gas discharge corresponds to a specific pressure regime inside the discharge tube: Cathode Glow occurs at ~10 mmHg, Striations form at ~1 mmHg in the positive column, and Crookes Dark Space expands to cover most of the tube at ~0.01 mmHg where cathode rays are freely emitted.

Adım Adım Çözüm

1
Identify the discharge stage for Cathode Glow.
Cathode glow occurs at moderate pressure (~10 mmHg) directly adjacent to the negative electrode.
Initial gas ionization near the cathode causes luminescence at this pressure stage.
2
Identify the discharge stage for Striations.
Striations represent light and dark divisions of the positive column at ~1 mmHg.
Periodic ionization and recombination along the tube produce alternating luminous discs.
3
Identify the discharge stage for Crookes Dark Space.
Crookes dark space expands as pressure drops to ~0.01 mmHg.
At very low pressures, electrons travel longer distances without colliding, causing the dark space to fill most of the discharge tube.

Anahtar Kavram

Stages of electric conduction through gases at reduced pressure.
Soru 7199Soru

Using differentiation from first principles, what is the derivative dydx\frac{\mathrm{d}y}{\mathrm{d}x} of the function f(x)=3x22xf(x) = 3x^2 - 2x?

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Cevap: 6x26x - 2

Cevap

The derivative of f(x)=3x22xf(x) = 3x^2 - 2x with respect to xx is 6x26x - 2.
Applying the first principles definition limh0f(x+h)f(x)h\lim_{h \to 0} \frac{f(x+h) - f(x)}{h} to f(x)=3x22xf(x) = 3x^2 - 2x yields 3x2+6xh+3h22x2h(3x22x)h=6xh+3h22hh=6x+3h2\frac{3x^2 + 6xh + 3h^2 - 2x - 2h - (3x^2 - 2x)}{h} = \frac{6xh + 3h^2 - 2h}{h} = 6x + 3h - 2. As h0h \to 0, this simplifies directly to 6x26x - 2.

Adım Adım Çözüm

1
Set up the definition of the derivative from first principles.
dydx=limh0f(x+h)f(x)h\frac{\mathrm{d}y}{\mathrm{d}x} = \lim_{h \to 0} \frac{f(x+h) - f(x)}{h}
The definition of the derivative is the limit of the difference quotient as hh approaches zero.
2
Substitute f(x+h)f(x+h) and f(x)f(x) into the difference quotient.
f(x+h)=3(x+h)22(x+h)=3(x2+2xh+h2)2x2h=3x2+6xh+3h22x2hf(x+h) = 3(x+h)^2 - 2(x+h) = 3(x^2 + 2xh + h^2) - 2x - 2h = 3x^2 + 6xh + 3h^2 - 2x - 2h
Expand (x+h)2(x+h)^2 completely using algebraic identity.
3
Subtract f(x)f(x) from f(x+h)f(x+h) to find the numerator.
f(x+h)f(x)=(3x2+6xh+3h22x2h)(3x22x)=6xh+3h22hf(x+h) - f(x) = (3x^2 + 6xh + 3h^2 - 2x - 2h) - (3x^2 - 2x) = 6xh + 3h^2 - 2h
Cancel out identical terms 3x23x^2 and 2x-2x.
4
Divide by hh and evaluate the limit as h0h \to 0.
\frac{6xh + 3h^2 - 2h}{h} = 6x + 3h - 2; \quad \lim_{h \to 0} (6x + 3h - 2) = 6x - 2
Factor out hh to cancel the denominator, then set h=0h = 0.

Anahtar Kavram

Differentiation from First Principles
Tahmini Süre:1m 30s
Soru 7200Soru

Calculate the numerical values of the following sequence and progression quantities, then arrange them in ascending order (from smallest to largest):

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Cevap

The correct ascending order of the numerical values is: the common ratio of the GP (value = 3), the common difference of the AP (value = 4), the 5th term of the AP (value = 8), and the sum to infinity of the GP (value = 10).
Evaluating each sequence property yields numerical values: the GP common ratio equals 3, the AP common difference equals 4, the AP 5th term equals 8, and the GP sum to infinity equals 10. Ordering these values from least to greatest produces the sequence 3, 4, 8, 10.

Adım Adım Çözüm

1
Calculate the value for the first quantity (AP common difference)
d=4d = 4
From a+6d=27a + 6d = 27 and a+2d=11a + 2d = 11, subtract to find 4d=16    d=44d = 16 \implies d = 4.
2
Calculate the value for the second quantity (GP common ratio)
r=3r = 3
From ar4=162ar^4 = 162 and ar=6ar = 6, divide to obtain r3=27    r=3r^3 = 27 \implies r = 3.
3
Calculate the value for the third quantity (GP sum to infinity)
S=10S_{\infty} = 10
Apply the sum to infinity formula S=a1r=510.5=10S_{\infty} = \frac{a}{1-r} = \frac{5}{1 - 0.5} = 10.
4
Calculate the value for the fourth quantity (AP 5th term)
T5=8T_5 = 8
Apply the nth term formula T5=a+4d=2+4(1.5)=8T_5 = a + 4d = 2 + 4(1.5) = 8.
5
Sort the calculated values in ascending order
3 < 4 < 8 < 10
Comparing the values gives 33 (GP common ratio), 44 (AP common difference), 88 (AP 5th term), and 1010 (GP sum to infinity).

Anahtar Kavram

Nth term, common difference, common ratio, and sum to infinity calculations for AP and GP sequences.
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