Tüm alıştırma soruları

13931 soru

Soru 4221Soru

A trapezium has parallel sides of lengths 8 cm8\text{ cm} and 12 cm12\text{ cm}. If the perpendicular distance between these parallel sides is 6 cm6\text{ cm}, what is the area of the trapezium?

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Cevap: 60 cm260\text{ cm}^2

Cevap

60 cm260\text{ cm}^2
The area of a trapezium is given by A=12(a+b)hA = \frac{1}{2}(a + b)h, where aa and bb are the parallel sides and hh is the perpendicular distance between them. Substituting a=8a = 8, b=12b = 12, and h=6h = 6 gives A=12(8+12)(6)=12(20)(6)=60 cm2A = \frac{1}{2}(8 + 12)(6) = \frac{1}{2}(20)(6) = 60\text{ cm}^2.

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1
Identify the given dimensions and the formula for the area of a trapezium.
Parallel sides a=8 cma = 8\text{ cm}, b=12 cmb = 12\text{ cm}, height h=6 cmh = 6\text{ cm}. Formula: A=12(a+b)hA = \frac{1}{2}(a + b)h.
The area of a trapezium depends on the sum of its parallel sides and its perpendicular height.
2
Sum the parallel sides.
a+b=8+12=20 cma + b = 8 + 12 = 20\text{ cm}.
The average of the parallel sides forms the effective width of an equivalent rectangle.
3
Multiply by half of the height to find the total area.
A=12×20×6=60 cm2A = \frac{1}{2} \times 20 \times 6 = 60\text{ cm}^2.
Completing the formula gives the exact plane surface measure in square centimeters.

Anahtar Kavram

Area of a Trapezium
Soru 4222Soru

Complete the sentence below by supplying the correct prepositions in the blanks.

Aşağıdaki boşlukları doldurun

The tribunal declared that the submitted documentation was completely bereft credible financial records, rendering the director's defence tantamount an outright admission of corruption.
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Cevap

The first blank requires 'of' to form the adjectival collocation 'bereft of', and the second blank requires 'to' to form the dependent prepositional structure 'tantamount to'.
The correct prepositions are 'of' for the first blank and 'to' for the second blank. In standard formal English, the adjective 'bereft' takes the dependent preposition 'of' to signify complete lack or deprivation. Similarly, the adjective 'tantamount' takes the fixed preposition 'to' when describing something that is equal in seriousness or significance to another thing.

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1
Determine the required dependent preposition for the adjective 'bereft'.
The adjective 'bereft' strictly requires the preposition 'of' when indicating a state of being deprived of or lacking something.
Prepositions such as 'with', 'from', or 'in' are ungrammatical collocations when paired with 'bereft'.
2
Determine the required preposition for the adjective 'tantamount'.
The adjective 'tantamount' obligatorily pairs with 'to' when denoting equivalence in meaning, force, or effect.
Using 'with', 'for', or 'of' after 'tantamount' violates standard English prepositional rules.

Anahtar Kavram

Dependent Prepositions and Adjectival Collocations
Soru 4223Soru

A micrometer screw gauge has a pitch of 0.5 mm0.5\text{ mm} and 5050 divisions on its circular thimble scale. When the anvil and spindle are brought into contact without an object between them, the 47th47\text{th} division on the thimble scale aligns exactly with the datum line of the main scale. When used to measure the diameter of a uniform metal rod, the main scale reads 1.5 mm1.5\text{ mm} and the 18th18\text{th} division on the thimble scale aligns with the datum line. What is the true diameter of the metal rod?

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Cevap: 1.71 mm1.71\text{ mm}

Cevap

The true diameter of the metal rod is 1.71 mm1.71\text{ mm}.
The least count of the micrometer is 0.01 mm0.01\text{ mm}. Because the zero position when closed shows the 47th47\text{th} division aligned, it has a negative zero error of 0.03 mm-0.03\text{ mm}. Subtracting this negative error from the observed reading of 1.68 mm1.68\text{ mm} gives 1.68(0.03)=1.71 mm1.68 - (-0.03) = 1.71\text{ mm}.

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1
Calculate the least count (precision) of the micrometer screw gauge.
Least count=PitchNumber of thimble divisions=0.5 mm50=0.01 mm\text{Least count} = \frac{\text{Pitch}}{\text{Number of thimble divisions}} = \frac{0.5\text{ mm}}{50} = 0.01\text{ mm}.
The least count determines the value of each thimble division.
2
Determine the zero error of the instrument.
Since the 47th47\text{th} division coincides with the datum line when closed, the zero mark lies above the reference line. Zero error=(5047)×0.01 mm=0.03 mm\text{Zero error} = -(50 - 47) \times 0.01\text{ mm} = -0.03\text{ mm}.
When the thimble zero mark has passed the datum line in the reverse direction, the instrument exhibits a negative zero error.
3
Calculate the observed reading from the main scale and thimble scale.
Observed reading=1.5 mm+(18×0.01 mm)=1.5 mm+0.18 mm=1.68 mm\text{Observed reading} = 1.5\text{ mm} + (18 \times 0.01\text{ mm}) = 1.5\text{ mm} + 0.18\text{ mm} = 1.68\text{ mm}.
The observed reading is the sum of the main scale reading and the thimble scale reading.
4
Compute the true reading by correcting for zero error.
True reading=Observed readingZero error=1.68 mm(0.03 mm)=1.71 mm\text{True reading} = \text{Observed reading} - \text{Zero error} = 1.68\text{ mm} - (-0.03\text{ mm}) = 1.71\text{ mm}.
True value is found by subtracting the zero error (including its sign) from the observed value.

Anahtar Kavram

Zero Error Correction in Micrometer Screw Gauge
Soru 4224Soru

The perpendicular bisector of the line segment joining the points P(2,1)P(2, -1) and Q(6,7)Q(6, 7) intersects the yy-axis at (0,c)(0, c). Find the value of cc.

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Cevap: 5

Cevap

The value of cc is 5.
The midpoint of PQPQ is (4,3)(4, 3) and the gradient of PQPQ is 22. The perpendicular bisector has a gradient of 12-\frac{1}{2} and passes through (4,3)(4, 3). Substituting these into the line equation gives y3=12(x4)y - 3 = -\frac{1}{2}(x - 4), which simplifies to y=12x+5y = -\frac{1}{2}x + 5. The line intersects the yy-axis at (0,5)(0, 5), so c=5c = 5.

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1
Find the midpoint of the line segment PQPQ
Midpoint M=(4,3)M = (4, 3)
The perpendicular bisector must pass through the midpoint of the segment.
2
Calculate the gradient of PQPQ
Gradient mPQ=2m_{PQ} = 2
Using the slope formula m=y2y1x2x1m = \frac{y_2 - y_1}{x_2 - x_1} for points (2,1)(2, -1) and (6,7)(6, 7).
3
Determine the gradient of the perpendicular line
Perpendicular gradient m=12m_{\perp} = -\frac{1}{2}
Perpendicular lines have gradients that are negative reciprocals (m1m2=1m_1 m_2 = -1).
4
Formulate the equation of the perpendicular bisector and solve for the yy-intercept
y=12x+5y = -\frac{1}{2}x + 5, hence c=5c = 5
Using point-slope form yy1=m(xx1)y - y_1 = m(x - x_1) with point (4,3)(4, 3) and m=12m = -\frac{1}{2}, setting x=0x = 0 gives the yy-intercept.

Anahtar Kavram

Perpendicular Bisector and Line Equations
Soru 4225Soru

The physical quantity impulse is defined as the product of force and time. Which of the following physical quantities has the same dimensions as impulse?

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Cevap: Linear momentum

Cevap

Linear momentum
Linear momentum is calculated as mass times velocity, which yields the base dimensions [MLT1][M L T^{-1}]. This is identical to impulse, which is force times time ([MLT2]×[T]=[MLT1][M L T^{-2}] \times [T] = [M L T^{-1}]).

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1
Determine the dimensions of impulse.
Impulse=Force×Time=[MLT2][T]=[MLT1]\text{Impulse} = \text{Force} \times \text{Time} = [M L T^{-2}][T] = [M L T^{-1}]
Force has base dimensions [MLT2][M L T^{-2}] and time has dimension [T][T].
2
Determine the dimensions of linear momentum.
Linear Momentum=Mass×Velocity=[M][LT1]=[MLT1]\text{Linear Momentum} = \text{Mass} \times \text{Velocity} = [M][L T^{-1}] = [M L T^{-1}]
Mass has base dimension [M][M] and velocity has dimensions [LT1][L T^{-1}].
3
Compare the dimensions of impulse and linear momentum.
Both quantities have identical dimensions of [MLT1][M L T^{-1}].
By the impulse-momentum theorem, impulse equals change in momentum.

Anahtar Kavram

Dimensional analysis of physical quantities
Soru 4226Soru

A body of mass 0.2 kg0.2\text{ kg} undergoes simple harmonic motion with an angular frequency of 10 rad/s10\text{ rad/s} and an amplitude of 0.04 m0.04\text{ m}. What is the magnitude of the maximum restoring force acting on the body in newtons?

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Cevap: 0.8

Cevap

The magnitude of the maximum restoring force acting on the body is 0.8 N0.8\text{ N}.
The maximum restoring force in simple harmonic motion occurs at maximum displacement (y=Ay = A) and is given by Fmax=mω2AF_{\text{max}} = m \omega^2 A. Substituting m=0.2 kgm = 0.2\text{ kg}, ω=10 rad/s\omega = 10\text{ rad/s}, and A=0.04 mA = 0.04\text{ m} yields Fmax=0.2×(10)2×0.04=0.8 NF_{\text{max}} = 0.2 \times (10)^2 \times 0.04 = 0.8\text{ N}.

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1
Identify the given physical quantities from the problem statement.
m=0.2 kgm = 0.2\text{ kg}, ω=10 rad/s\omega = 10\text{ rad/s}, and A=0.04 mA = 0.04\text{ m}.
These parameters are required to calculate acceleration and restoring force in simple harmonic motion.
2
Calculate the maximum acceleration of the oscillating body.
amax=ω2A=(10)2×0.04=4.0 m/s2a_{\text{max}} = \omega^2 A = (10)^2 \times 0.04 = 4.0\text{ m/s}^2.
In simple harmonic motion, maximum acceleration occurs at maximum displacement (the amplitude).
3
Determine the maximum restoring force.
Fmax=mamax=0.2×4.0=0.8 NF_{\text{max}} = m a_{\text{max}} = 0.2 \times 4.0 = 0.8\text{ N}.
According to Newton's second law, force is the product of mass and acceleration.

Anahtar Kavram

Maximum Restoring Force in Simple Harmonic Motion
Soru 4227Soru

If y=e2xcos3xy = e^{2x} \cos 3x, what is dydx\frac{dy}{dx}?

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Cevap: e2x(2cos3x3sin3x)e^{2x}(2\cos 3x - 3\sin 3x)

Cevap

dydx=e2x(2cos3x3sin3x)\frac{dy}{dx} = e^{2x}(2\cos 3x - 3\sin 3x)
Applying the product rule to u=e2xu = e^{2x} and v=cos3xv = \cos 3x yields dudx=2e2x\frac{du}{dx} = 2e^{2x} and dvdx=3sin3x\frac{dv}{dx} = -3\sin 3x. Substituting these into udvdx+vdudxu\frac{dv}{dx} + v\frac{du}{dx} gives e2x(3sin3x)+cos3x(2e2x)=e2x(2cos3x3sin3x)e^{2x}(-3\sin 3x) + \cos 3x(2e^{2x}) = e^{2x}(2\cos 3x - 3\sin 3x).

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1
Identify the components for the product rule
Let u=e2xu = e^{2x} and v=cos3xv = \cos 3x.
The function y=e2xcos3xy = e^{2x} \cos 3x is a product of two differentiable functions.
2
Differentiate u=e2xu = e^{2x} with respect to xx
dudx=2e2x\frac{du}{dx} = 2e^{2x}
By the chain rule, ddx(ekx)=kekx\frac{d}{dx}(e^{kx}) = k e^{kx}.
3
Differentiate v=cos3xv = \cos 3x with respect to xx
dvdx=3sin3x\frac{dv}{dx} = -3\sin 3x
By the chain rule, ddx(coskx)=ksinkx\frac{d}{dx}(\cos kx) = -k \sin kx.
4
Apply the product rule formula dydx=udvdx+vdudx\frac{dy}{dx} = u \frac{dv}{dx} + v \frac{du}{dx} and factor out e2xe^{2x}
\frac{dy}{dx} = e^{2x}(-3\sin 3x) + (\cos 3x)(2e^{2x}) = e^{2x}(2\cos 3x - 3\sin 3x)
Combining the products and factoring out the common exponential factor simplifies the expression.

Anahtar Kavram

Product Rule and Chain Rule for Exponential and Trigonometric Functions
Soru 4228Soru

If log10(x)+log10(5)=2\log_{10}(x) + \log_{10}(5) = 2, what is the value of xx?

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Cevap: 20

Cevap

20
Using the logarithmic product identity logb(A)+logb(B)=logb(AB)\log_b(A) + \log_b(B) = \log_b(AB), the left side simplifies to log10(5x)=2\log_{10}(5x) = 2. Converting to exponential form gives 5x=102=1005x = 10^2 = 100, which simplifies directly to x=20x = 20.

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1
Apply the product law of logarithms
log10(5x)=2\log_{10}(5x) = 2
The sum of logarithms with the same base equals the logarithm of their product: logb(A)+logb(B)=logb(AB)\log_b(A) + \log_b(B) = \log_b(AB).
2
Convert the logarithmic equation to exponential form
5x=102=1005x = 10^2 = 100
By definition of logarithms, if logb(y)=c\log_b(y) = c, then y=bcy = b^c.
3
Solve for xx
x=1005=20x = \frac{100}{5} = 20
Divide both sides of the linear equation by 55.

Anahtar Kavram

Logarithmic Product Law and Exponential Conversion
Tahmini Süre:45s
Soru 4229Soru

If 75+1227=k3\sqrt{75} + \sqrt{12} - \sqrt{27} = k\sqrt{3}, what is the value of kk?

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Cevap: 4

Cevap

The value of kk is 4.
Simplifying each surd into its basic form yields 75=53\sqrt{75} = 5\sqrt{3}, 12=23\sqrt{12} = 2\sqrt{3}, and 27=33\sqrt{27} = 3\sqrt{3}. Combining the coefficients gives (5+23)3=43(5 + 2 - 3)\sqrt{3} = 4\sqrt{3}. Equating 434\sqrt{3} to k3k\sqrt{3} shows that k=4k = 4.

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1
Simplify each individual surd by factoring out perfect squares
75=53\sqrt{75} = 5\sqrt{3}, 12=23\sqrt{12} = 2\sqrt{3}, 27=33\sqrt{27} = 3\sqrt{3}
To combine surds through addition or subtraction, they must be converted to similar surds.
2
Combine the coefficients of the like surds
53+2333=(5+23)3=435\sqrt{3} + 2\sqrt{3} - 3\sqrt{3} = (5 + 2 - 3)\sqrt{3} = 4\sqrt{3}
Like terms with the same radical factor 3\sqrt{3} can be added and subtracted directly.
3
Compare the resulting coefficient with k3k\sqrt{3}
k=4k = 4
By direct comparison of coefficients of 3\sqrt{3}, kk equals 4.

Anahtar Kavram

Simplification and combining of similar surds
Soru 4230Soru

Two 2×22 \times 2 matrices are given as A=(2143)A = \begin{pmatrix} 2 & -1 \\ 4 & 3 \end{pmatrix} and B=(102k)B = \begin{pmatrix} 1 & 0 \\ 2 & k \end{pmatrix}. If the determinant of the product matrix ABAB is equal to 3030, what is the value of kk?

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Cevap: 3

Cevap

The value of k is 3.
The determinant of a product of square matrices equals the product of their individual determinants: det(AB)=det(A)det(B)\det(AB) = \det(A) \cdot \det(B). Evaluating det(A)\det(A) yields (2)(3)(1)(4)=10(2)(3) - (-1)(4) = 10, and det(B)\det(B) yields (1)(k)(0)(2)=k(1)(k) - (0)(2) = k. Substituting these into det(AB)=30\det(AB) = 30 gives 10k=3010k = 30, leading directly to k=3k = 3.

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1
Evaluate the determinant of matrix A
\det(A) = 10
Using the 2×22 \times 2 determinant formula det(abcd)=adbc\det\begin{pmatrix} a & b \\ c & d \end{pmatrix} = ad - bc, we calculate det(A)=(2)(3)(1)(4)=6+4=10\det(A) = (2)(3) - (-1)(4) = 6 + 4 = 10.
2
Evaluate the determinant of matrix B
\det(B) = k
Calculating the determinant of matrix BB yields det(B)=(1)(k)(0)(2)=k\det(B) = (1)(k) - (0)(2) = k.
3
Use the product property of determinants to solve for k
k = 3
Since det(AB)=det(A)det(B)\det(AB) = \det(A) \cdot \det(B), we have 10k=3010k = 30. Dividing both sides by 10 yields k=3k = 3.

Anahtar Kavram

Determinant of Matrix Product
Tahmini Süre:1m 30s
Soru 4231Soru

The sum of the first nn terms of an arithmetic progression (AP) is given by Sn=2n2+3nS_n = 2n^2 + 3n. The 3rd3^{\text{rd}} term of this AP is equal to the 2nd2^{\text{nd}} term of a geometric progression (GP). If the common ratio of the GP is 22, what is the sum of the first 44 terms of the GP?

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Cevap: 97.597.5

Cevap

97.597.5
Evaluating S3S2S_3 - S_2 gives the 3rd AP term as 2714=1327 - 14 = 13. Setting the 2nd GP term a(2)=13a(2) = 13 yields a=6.5a = 6.5. The sum of the first 4 terms of the GP is 6.5×(241)=6.5×15=97.56.5 \times (2^4 - 1) = 6.5 \times 15 = 97.5.

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1
Find the 3rd term (T3T_3) of the AP using the given sum formula Sn=2n2+3nS_n = 2n^2 + 3n
T3=S3S2=[2(3)2+3(3)][2(2)2+3(2)]=[18+9][8+6]=2714=13T_3 = S_3 - S_2 = [2(3)^2 + 3(3)] - [2(2)^2 + 3(2)] = [18 + 9] - [8 + 6] = 27 - 14 = 13
The nn-th term of a sequence is equal to SnSn1S_n - S_{n-1}.
2
Determine the first term (aa) of the GP
Since G2=13G_2 = 13 and common ratio r=2r = 2, ar21=13    2a=13    a=6.5a \cdot r^{2-1} = 13 \implies 2a = 13 \implies a = 6.5
The nn-th term of a GP is given by Gn=arn1G_n = a r^{n-1}.
3
Calculate the sum of the first 4 terms of the GP
S4=a(r41)r1=6.5(241)21=6.5×15=97.5S_4 = \frac{a(r^4 - 1)}{r - 1} = \frac{6.5(2^4 - 1)}{2 - 1} = 6.5 \times 15 = 97.5
The sum of the first nn terms of a GP with r>1r > 1 is Sn=a(rn1)r1S_n = \frac{a(r^n - 1)}{r - 1}.

Anahtar Kavram

Combining Arithmetic Progression sum formula with Geometric Progression term and sum formulas
Tahmini Süre:2m 0s
Soru 4232Soru

The table below shows the frequency distribution of marks obtained by a group of students in a mathematics test:

Mark (xx)246810
Frequency (ff)21412

Find the mean deviation of the distribution.

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Cevap: 2

Cevap

The mean deviation of the distribution is 2.
To find the mean deviation, first calculate the mean xˉ=fxf=6010=6\bar{x} = \frac{\sum fx}{\sum f} = \frac{60}{10} = 6. Next, sum the absolute deviations multiplied by their frequencies: fxxˉ=2(4)+1(2)+4(0)+1(2)+2(4)=20\sum f|x - \bar{x}| = 2(4) + 1(2) + 4(0) + 1(2) + 2(4) = 20. Dividing this total by the sum of frequencies 1010 yields a mean deviation of 22.

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1
Calculate the arithmetic mean of the distribution
\bar{x} = \frac{\sum f x}{\sum f} = \frac{(2 \times 2) + (1 \times 4) + (4 \times 6) + (1 \times 8) + (2 \times 10)}{2 + 1 + 4 + 1 + 2} = \frac{60}{10} = 6
The mean is required as the central benchmark from which individual deviations are measured.
2
Calculate the sum of absolute deviations weighted by frequency
\sum f |x - \bar{x}| = 2|2 - 6| + 1|4 - 6| + 4|6 - 6| + 1|8 - 6| + 2|10 - 6| = 8 + 2 + 0 + 2 + 8 = 20
Each absolute difference from the mean must be multiplied by its frequency to account for the total deviation.
3
Divide the total absolute deviation by the total frequency
\text{Mean Deviation} = \frac{\sum f |x - \bar{x}|}{\sum f} = \frac{20}{10} = 2
The mean deviation represents the average distance of all observations from the arithmetic mean.

Anahtar Kavram

Mean Deviation of a Frequency Distribution
Tahmini Süre:1m 30s
Soru 4233Soru

The mechanical power PP dissipated by a circular disc of radius RR rotating at an angular velocity ω\omega in a fluid of density ρ\rho is given by the relation P=kρaωbRcP = k \cdot \rho^a \cdot \omega^b \cdot R^c, where kk is a dimensionless constant. Using dimensional analysis, which of the following represents the correct values of the exponents aa, bb, and cc?

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Cevap: a=1,b=3,c=5a = 1, b = 3, c = 5

Cevap

a=1,b=3,c=5a = 1, b = 3, c = 5
By writing the dimensions of power as [ML2T3][M L^2 T^{-3}], density as [ML3][M L^{-3}], angular velocity as [T1][T^{-1}], and radius as [L][L], dimensional homogeneity requires that ML2T3=MaL3a+cTbM L^2 T^{-3} = M^a L^{-3a + c} T^{-b}. Equating powers gives a=1a = 1, b=3b = 3, and c=5c = 5.

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1
Express the base dimensions for each physical quantity
Power [P]=ML2T3[P] = M L^2 T^{-3}, Density [ρ]=ML3[\rho] = M L^{-3}, Angular velocity [ω]=T1[\omega] = T^{-1}, and Radius [R]=L[R] = L.
Dimensional analysis requires decomposing derived physical quantities into fundamental dimensions of mass (MM), length (LL), and time (TT).
2
Substitute dimensions into the given equation P=kρaωbRcP = k \cdot \rho^a \cdot \omega^b \cdot R^c
ML2T3=(ML3)a(T1)b(L)c=MaL3a+cTbM L^2 T^{-3} = (M L^{-3})^a \cdot (T^{-1})^b \cdot (L)^c = M^a \cdot L^{-3a + c} \cdot T^{-b}.
The constant kk is dimensionless, so its dimension is 1.
3
Equate the powers of MM, LL, and TT on both sides of the equation
For mass MM: a=1a = 1. For time TT: b=3    b=3-b = -3 \implies b = 3. For length LL: 3a+c=2    3(1)+c=2    c=5-3a + c = 2 \implies -3(1) + c = 2 \implies c = 5.
According to the principle of dimensional homogeneity, powers of fundamental dimensions must be equal on both sides of a physically correct equation.

Anahtar Kavram

Dimensional Homogeneity and Formula Derivation
Tahmini Süre:2m 0s
Soru 4234Soru

Complete the sentence below by supplying a word nearest in meaning to the underlined word 'surreptitious'.

Aşağıdaki boşlukları doldurun

The auditor noted the treasurer's surreptitious transfer of company funds, observing that the transactions were executed in a completely manner to evade detection.
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Cevap

A suitable word nearest in meaning to 'surreptitious' is 'stealthy' (or 'furtive', 'clandestine', 'covert', 'secret').
In this context, 'surreptitious' means done, made, or acquired by stealth or secret means. Words like 'stealthy', 'furtive', 'clandestine', and 'covert' directly capture this meaning of acting secretly to avoid observation.

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1
Analyze the context of the sentence
The word 'surreptitious' describes actions performed quietly, secretly, or evasively to avoid being noticed or detected.
Understanding the context of financial transactions designed to avoid detection clarifies the required meaning.
2
Identify synonymous terms
Terms such as 'stealthy', 'furtive', 'clandestine', or 'covert' accurately describe actions taken secretly.
The correct replacement must maintain the sense of concealment and stealth expressed by the target word.

Anahtar Kavram

Synonyms and Words Nearest in Meaning
Tahmini Süre:1m 0s
Soru 4235Soru

In the dimensional equation for the period of oscillation of a simple pendulum, T=kgalbT = k g^a l^b, where TT is the period, gg is the acceleration due to gravity, ll is the length of the pendulum, and kk is a dimensionless constant, what is the numerical value of the exponent aa?

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Cevap: -0.5

Cevap

The numerical value of the exponent aa is -0.5.
Applying dimensional analysis to T=kgalbT = k g^a l^b, the dimension of the left-hand side is T1\text{T}^1. The right-hand side has dimensions (L T2)a(L)b=La+bT2a(\text{L T}^{-2})^a (\text{L})^b = \text{L}^{a+b} \text{T}^{-2a}. Equating the exponents of time T\text{T} yields 1=2a1 = -2a, which gives a=0.5a = -0.5.

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1
Express the dimensions of all physical quantities involved in fundamental base dimensions (M, L, T).
The dimension of period TT is [T][\text{T}], length ll is [L][\text{L}], and gravitational acceleration gg is [L T2][\text{L T}^{-2}].
Dimensional analysis requires substituting each quantity with its fundamental dimensions.
2
Formulate the dimensional homogeneity equation.
M0L0T1=(L T2)a(L)b=La+bT2a\text{M}^0 \text{L}^0 \text{T}^1 = (\text{L T}^{-2})^a (\text{L})^b = \text{L}^{a+b} \text{T}^{-2a}.
The principle of dimensional homogeneity states that the exponents of base dimensions on both sides of a physically correct equation must be equal.
3
Equate exponents of time T\text{T} and solve for aa.
1=2a    a=12=0.51 = -2a \implies a = -\frac{1}{2} = -0.5.
Comparing the powers of T\text{T} gives a linear equation in aa.

Anahtar Kavram

Principle of Dimensional Homogeneity
Tahmini Süre:1m 15s
Soru 4236Soru

The investigative panel noted that leaking confidential executive files prior to the hearing would be highly prejudicial _____ the proceedings and completely subversive _____ established board protocol. Which pair of prepositions correctly completes the sentence?

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Cevap: to / of

Cevap

The pair 'to / of' correctly completes the sentence because 'prejudicial to' and 'subversive of' are the fixed, standard prepositional collocations.
The correct option provides the exact prepositional collocations required by the adjectives: 'prejudicial to' means harmful or damaging to an outcome, and 'subversive of' means seeking to undermine an established authority or protocol.

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1
Identify the dependent preposition required by the formal adjective 'prejudicial'.
In formal academic and legal contexts, 'prejudicial' requires the preposition 'to' when taking an object (e.g., prejudicial to the proceedings).
Adjectives denoting harm or detriment, such as 'prejudicial', 'inimical', and 'detrimental', grammatically govern 'to'.
2
Identify the dependent preposition required by the adjective 'subversive'.
The adjective 'subversive' requires the preposition 'of' when followed by a noun phrase complement (e.g., subversive of protocol).
Adjectives and nouns indicating destruction, undermining, or overthrowing typically collocate with 'of'.

Anahtar Kavram

Dependent prepositions following adjectives of impact and subversion
Soru 4237Soru

A sector of a circle of radius 14 cm14\text{ cm} subtends an angle of 9090^\circ at the centre of the circle. What is the area of the sector in cm2\text{cm}^2? (Take π=227\pi = \frac{22}{7})

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Cevap: 154

Cevap

The area of the sector is 154 cm2154\text{ cm}^2.
The area of a circular sector is given by Area=θ360×πr2\text{Area} = \frac{\theta}{360^\circ} \times \pi r^2. Substituting θ=90\theta = 90^\circ, r=14 cmr = 14\text{ cm}, and π=227\pi = \frac{22}{7} yields 90360×227×142=14×616=154 cm2\frac{90}{360} \times \frac{22}{7} \times 14^2 = \frac{1}{4} \times 616 = 154\text{ cm}^2.

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1
Identify the formula for the area of a circular sector.
Area=θ360×πr2\text{Area} = \frac{\theta}{360^\circ} \times \pi r^2
The area of a sector is proportional to the central angle it subtends relative to a full circle (360360^\circ).
2
Substitute the given values into the formula.
Area=90360×227×(14)2\text{Area} = \frac{90^\circ}{360^\circ} \times \frac{22}{7} \times (14)^2
Given radius r=14 cmr = 14\text{ cm}, angle θ=90\theta = 90^\circ, and π=227\pi = \frac{22}{7}.
3
Simplify the fraction and calculate the numerical value.
Area=14×227×196=14×22×28=22×7=154 cm2\text{Area} = \frac{1}{4} \times \frac{22}{7} \times 196 = \frac{1}{4} \times 22 \times 28 = 22 \times 7 = 154\text{ cm}^2
Simplifying 90360\frac{90}{360} yields 14\frac{1}{4} and dividing 196196 by 77 gives 2828.

Anahtar Kavram

Area of a sector of a circle
Tahmini Süre:45s
Soru 4238Soru

A curve is defined by the equation y=x26x+11y = x^2 - 6x + 11. What is the minimum value of yy on this curve?

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Cevap: 2

Cevap

The minimum value of yy on the curve is 2.
Differentiating y=x26x+11y = x^2 - 6x + 11 gives dydx=2x6\frac{dy}{dx} = 2x - 6. Setting this derivative to zero yields 2x6=02x - 6 = 0, so x=3x = 3. Substituting x=3x = 3 into the original function gives y=(3)26(3)+11=2y = (3)^2 - 6(3) + 11 = 2. Since d2ydx2=2>0\frac{d^2y}{dx^2} = 2 > 0, the point at x=3x = 3 is a local minimum, making 2 the minimum value of yy.

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1
Find the first derivative of the curve function.
dydx=2x6\frac{dy}{dx} = 2x - 6
Stationary points occur where the derivative is equal to zero.
2
Solve for the xx-coordinate at the stationary point.
2x - 6 = 0 \implies x = 3
Setting the derivative to zero determines the input value where the slope is horizontal.
3
Calculate the corresponding yy-value at x=3x = 3.
y = (3)^2 - 6(3) + 11 = 2
Evaluating the original equation at x=3x = 3 yields the minimum value of yy.

Anahtar Kavram

Finding the minimum value of a function using differentiation
Soru 4239Soru

Given the matrices A=(231m)A = \begin{pmatrix} 2 & 3 \\ 1 & m \end{pmatrix} and B=(42)B = \begin{pmatrix} 4 \\ -2 \end{pmatrix}, if the matrix product AB=(26)AB = \begin{pmatrix} 2 \\ 6 \end{pmatrix}, what is the value of mm?

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Cevap: 1-1

Cevap

The value of mm is 1-1.
Multiplying the 2×22 \times 2 matrix by the 2×12 \times 1 column vector yields a 2×12 \times 1 result where the second row entry is 1(4)+m(2)=42m1(4) + m(-2) = 4 - 2m. Setting this equal to the second row element 66 gives 42m=64 - 2m = 6, which simplifies to m=1m = -1.

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1
Compute the matrix product ABAB
AB=(2(4)+3(2)1(4)+m(2))=(8642m)=(242m)AB = \begin{pmatrix} 2(4) + 3(-2) \\ 1(4) + m(-2) \end{pmatrix} = \begin{pmatrix} 8 - 6 \\ 4 - 2m \end{pmatrix} = \begin{pmatrix} 2 \\ 4 - 2m \end{pmatrix}
Matrix multiplication requires taking the dot product of each row of the first matrix with the column vector.
2
Equate the resulting vector to the given vector (26)\begin{pmatrix} 2 \\ 6 \end{pmatrix}
42m=64 - 2m = 6
Corresponding elements of equal matrices must be equal.
3
Solve the linear equation for mm
2m=642m=2m=1-2m = 6 - 4 \Rightarrow -2m = 2 \Rightarrow m = -1
Isolating the variable mm by subtracting 44 from both sides and dividing by 2-2.

Anahtar Kavram

Matrix Multiplication and Equality of Matrices
Soru 4240Soru

The distribution of daily solar energy generation (in kWh) recorded at an agricultural research station over a period of days is summarized in the table below:

Daily Generation (kWh)Frequency (ff)
101910 - 1933
202920 - 29xx
303930 - 3988
404940 - 4955
505950 - 59x+2x + 2

If the mean daily solar energy generation for the recorded period is 37.5 kWh37.5\text{ kWh}, what is the value of xx?

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Cevap: 66

Cevap

66
The exact class marks are 14.5,24.5,34.5,44.5,14.5, 24.5, 34.5, 44.5, and 54.554.5. The total frequency is f=18+2x\sum f = 18 + 2x and the sum of products is fx=651+79x\sum f x = 651 + 79x. Substituting these into xˉ=fxf\bar{x} = \frac{\sum f x}{\sum f} with xˉ=37.5\bar{x} = 37.5 gives 675+75x=651+79x675 + 75x = 651 + 79x, which solves to 4x=244x = 24, giving the value 66.

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1
Determine the class mark (midpoint xix_i) for each class interval
The midpoints are 14.5,24.5,34.5,44.5,14.5, 24.5, 34.5, 44.5, and 54.554.5.
The class mark is calculated as Lower Limit+Upper Limit2\frac{\text{Lower Limit} + \text{Upper Limit}}{2}.
2
Calculate total frequency f\sum f and total product sum fxi\sum f x_i
f=3+x+8+5+(x+2)=18+2x\sum f = 3 + x + 8 + 5 + (x + 2) = 18 + 2x.
fxi=3(14.5)+x(24.5)+8(34.5)+5(44.5)+(x+2)(54.5)=43.5+24.5x+276+222.5+54.5x+109=651+79x\sum f x_i = 3(14.5) + x(24.5) + 8(34.5) + 5(44.5) + (x+2)(54.5) = 43.5 + 24.5x + 276 + 222.5 + 54.5x + 109 = 651 + 79x
To compute the mean of grouped data, sum the products of each frequency and its corresponding class mark.
3
Set up the mean formula equation and solve for xx
xˉ=fxif    37.5=651+79x18+2x\bar{x} = \frac{\sum f x_i}{\sum f} \implies 37.5 = \frac{651 + 79x}{18 + 2x}
37.5(18+2x)=651+79x37.5(18 + 2x) = 651 + 79x
675+75x=651+79x675 + 75x = 651 + 79x
79x75x=67565179x - 75x = 675 - 651
4x=24    x=64x = 24 \implies x = 6
Equating the expression for mean to the given mean value 37.5 kWh37.5\text{ kWh} yields a linear equation in xx.

Anahtar Kavram

Measures of Central Tendency for Grouped Data - Finding Unknown Frequencies from Grouped Mean
ÖncekiSayfa 212 / 697Sonraki
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