Q. The quadratic equation x^2 + 6x + 9 = 0 has roots that are:
A.
Real and equal
B.
Real and distinct
C.
Complex
D.
None of these
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Solution
The discriminant is 0, hence the roots are real and equal.
Correct Answer: A — Real and equal
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Q. The quadratic equation x^2 + kx + 16 = 0 has equal roots. What is the value of k?
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Solution
For equal roots, the discriminant must be zero: k^2 - 4*1*16 = 0, solving gives k = -8.
Correct Answer: A — -8
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Q. The quadratic equation x^2 + px + q = 0 has roots 3 and -2. What is the value of p?
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Solution
Using the sum of roots: p = -(3 + (-2)) = -1.
Correct Answer: B — 5
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Q. The quadratic equation x^2 - 3x + 2 = 0 can be factored as?
A.
(x-1)(x-2)
B.
(x-2)(x-1)
C.
(x+1)(x+2)
D.
(x-3)(x+2)
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Solution
The equation factors to (x-1)(x-2) = 0.
Correct Answer: A — (x-1)(x-2)
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Q. The quadratic equation x^2 - 4x + 4 = 0 has how many distinct real roots?
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Solution
The discriminant is 0, indicating one distinct real root.
Correct Answer: B — 1
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Q. The quadratic equation x^2 - 6x + 9 = 0 has how many distinct real roots?
A.
0
B.
1
C.
2
D.
Infinite
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Solution
The discriminant is 0, indicating that there is exactly one distinct real root.
Correct Answer: B — 1
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Q. The quadratic equation x^2 - 6x + k = 0 has roots that are both positive. What is the condition on k?
A.
k > 0
B.
k < 0
C.
k > 9
D.
k < 9
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Solution
For both roots to be positive, k must be greater than the square of half the coefficient of x: k > (6/2)^2 = 9.
Correct Answer: C — k > 9
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Q. The quadratic equation x^2 - 6x + k = 0 has roots that differ by 2. What is the value of k?
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Solution
Let the roots be r and r+2. Then, r + (r+2) = 6 and r(r+2) = k. Solving gives k = 10.
Correct Answer: B — 10
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Q. The range of sin^(-1)(x) is:
A.
[-π/2, π/2]
B.
[0, π]
C.
[-1, 1]
D.
[0, 1]
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Solution
The range of sin^(-1)(x) is [-π/2, π/2].
Correct Answer: A — [-π/2, π/2]
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Q. The range of the data set 1, 3, 5, 7, 9 is:
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Solution
Range = Maximum - Minimum = 9 - 1 = 8.
Correct Answer: A — 8
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Q. The range of the data set {10, 15, 20, 25, 30} is?
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Solution
Range = Maximum value - Minimum value = 30 - 10 = 20.
Correct Answer: A — 15
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Q. The range of the function f(x) = |x - 1| is:
A.
(-∞, 1)
B.
[0, ∞)
C.
(-1, 1)
D.
[1, ∞)
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Solution
The absolute value function has a minimum value of 0, hence the range is [0, ∞).
Correct Answer: B — [0, ∞)
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Q. The range of the function y = sin^(-1)(x) is:
A.
(0, π)
B.
[-π/2, π/2]
C.
[-1, 1]
D.
[0, 1]
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Solution
The range of y = sin^(-1)(x) is [-π/2, π/2].
Correct Answer: B — [-π/2, π/2]
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Q. The rate law for a reaction is determined experimentally and is dependent on which of the following?
A.
Stoichiometry of the reaction
B.
Mechanism of the reaction
C.
Equilibrium constant
D.
Temperature only
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Solution
The rate law for a reaction is determined experimentally and is dependent on the mechanism of the reaction.
Correct Answer: B — Mechanism of the reaction
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Q. The rate law for a reaction is determined experimentally. Which of the following is true?
A.
It can be derived from stoichiometry
B.
It is always first-order
C.
It depends on the mechanism
D.
It is independent of temperature
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Solution
The rate law for a reaction depends on the mechanism of the reaction.
Correct Answer: C — It depends on the mechanism
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Q. The rate law for a reaction is given as rate = k[A][B]². What is the overall order of the reaction?
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Solution
The overall order of the reaction is the sum of the powers of the concentration terms, which is 1 + 2 = 3.
Correct Answer: C — 3
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Q. The rate of a reaction doubles when the temperature is increased by 10°C. This is an example of which rule?
A.
Arrhenius equation
B.
Van 't Hoff rule
C.
Le Chatelier's principle
D.
Gibbs free energy
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Solution
This is an example of Van 't Hoff rule, which states that the rate of reaction doubles for every 10°C increase in temperature.
Correct Answer: B — Van 't Hoff rule
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Q. The rate of a reaction is defined as the change in concentration of a reactant or product per unit time. What is the unit of rate?
A.
mol/L
B.
mol/L·s
C.
L/mol·s
D.
1/s
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Solution
The rate of reaction is expressed in terms of concentration change per unit time, hence the unit is mol/L·s.
Correct Answer: B — mol/L·s
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Q. The rate of a reaction is directly proportional to the product of the concentrations of the reactants raised to their respective powers. This is known as what?
A.
Rate law
B.
Equilibrium constant
C.
Reaction quotient
D.
Catalytic law
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Solution
This relationship is known as the rate law of the reaction.
Correct Answer: A — Rate law
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Q. The rate of heat transfer by conduction is directly proportional to the area and the temperature gradient. This is described by which law?
A.
Newton's Law of Cooling
B.
Fourier's Law of Heat Conduction
C.
Stefan-Boltzmann Law
D.
Ohm's Law
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Solution
Fourier's Law of Heat Conduction states that the rate of heat transfer by conduction is directly proportional to the area and the temperature gradient.
Correct Answer: B — Fourier's Law of Heat Conduction
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Q. The rate of heat transfer by conduction is directly proportional to which of the following?
A.
Temperature difference
B.
Surface area
C.
Material thickness
D.
All of the above
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Solution
The rate of heat transfer by conduction is directly proportional to the temperature difference between the two ends.
Correct Answer: A — Temperature difference
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Q. The real part of the complex number z = 4 - 3i is?
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Solution
The real part of z = 4 - 3i is 4.
Correct Answer: A — 4
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Q. The restoring force in a simple harmonic motion is directly proportional to:
A.
Displacement
B.
Velocity
C.
Time
D.
Mass
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Solution
Restoring force F = -kx, where k is the spring constant and x is the displacement.
Correct Answer: A — Displacement
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Q. The right-hand rule is used to determine the direction of?
A.
Magnetic field
B.
Current
C.
Force
D.
All of the above
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Solution
The right-hand rule can be used to determine the direction of the magnetic field, current, and force in electromagnetic situations.
Correct Answer: D — All of the above
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Q. The RMS speed of a gas is 250 m/s. What is the kinetic energy per molecule of the gas?
A.
0.5 * m * (250)^2
B.
0.25 * m * (250)^2
C.
0.75 * m * (250)^2
D.
1.5 * m * (250)^2
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Solution
The kinetic energy per molecule is given by KE = (1/2) * m * v^2. Thus, KE = 0.5 * m * (250)^2.
Correct Answer: A — 0.5 * m * (250)^2
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Q. The RMS speed of a gas is 300 m/s. What is the speed of sound in the gas if the ratio of specific heats is 1.4?
A.
300 m/s
B.
400 m/s
C.
500 m/s
D.
600 m/s
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Solution
Speed of sound = sqrt(γRT/M) = sqrt(1.4 * (300^2)) = 400 m/s.
Correct Answer: B — 400 m/s
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Q. The RMS speed of a gas is 400 m/s. What is the speed of sound in the gas if the ratio of specific heats is 1.4?
A.
400 m/s
B.
560 m/s
C.
700 m/s
D.
800 m/s
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Solution
The speed of sound in a gas is given by c = sqrt(γRT/M). For an ideal gas, c is approximately 1.4 times the RMS speed.
Correct Answer: B — 560 m/s
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Q. The roots of the equation 2x^2 - 4x + 1 = 0 are:
A.
1
B.
2
C.
1/2
D.
None of these
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Solution
Using the quadratic formula, x = [4 ± √(16 - 8)] / 4 = [4 ± 2√2] / 4 = 1 ± √2/2. Hence, the roots are not simple fractions.
Correct Answer: C — 1/2
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Q. The roots of the equation 2x^2 - 4x + k = 0 are 1 and 2. Find the value of k.
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Solution
Using Vieta's formulas, sum of roots = 1 + 2 = 3 = -(-4)/2 => k = 2*1*2 = 4.
Correct Answer: C — 6
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Q. The roots of the equation 5x^2 - 20x + 15 = 0 are:
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Solution
Using the quadratic formula, the roots are x = [20 ± √(400 - 300)] / 10 = [20 ± 10] / 10 = 3 and 1.
Correct Answer: B — 2
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