English Bihar (TRE 1.0) -2023
Q01. Let C be the circle (x – 1)2 + y2 = 1, oriented counter-clockwise. Then the value of the line integral. ∫ 3 4 C 4 – xy dx + x dy 3 is
A 6π
B 8π
C 12π
D More than one of the above
E None of the above
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Correct answer: 8π
English Bihar (TRE 1.0) -2023
Q02. The equation xy – z log y + exz = 1 can be solved in a neighborhood of the point (0, 1, 1) as y = f(x, z) for some continuously differentiable function f. Then
A ∇f(0, 1) = (2, 0)
B ∇f(0, 1) = (0, 2)
C ∇f(0, 1) = (0, 1)
D More than one of the above
E None of the above
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Correct answer: ∇f(0, 1) = (2, 0)
English Bihar (TRE 1.0) -2023
Q03. Let V be the solid region in 3 ℝ bounded by the paraboloid y = (x2 + z2) and the plane y = 4. Then the value of ∫∫∫ 2 2 V 15 x + z dV is y = (x2 + z2) continuous
A 128π
B 64π
C 28π
D More than one of the above
E None of the above
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Correct answer: 128π
Q04. If H = x î + 2y ĵ`+3z k̂ than ˆ ∫∫s H.nds is equal to (where A is the volume enclosed by S) –
A 3A
B 6A
C A
D 4A
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Correct answer: 6A
Q05. If a is differentiable vector point function and u is a differentiable scalar point function, then ∇ × (u a) is equal to -
A (∇ u) × a +u(∇ × a)
B (∇ × a). a +u(∇ × a)
C ∇ u. a +u(∇ × a)
D ∇ u × a +u. (∇ × a)
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Correct answer: (∇ u) × a +u(∇ × a)
Q06. If f1 and f2 are differentiable scalar functions and v is differentiable vector function such that f1v = ∇ f2, then v. curl v is -
A 1 f f f 2 2 1 f1 ∇ + ∇
B 1 1 f f 2 1 f f 1 2 ∇ − ∇
C 1 1 f f 2 2 f f 1 2 ∇ + ×∇
D Zero
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Correct answer: Zero
Q07. Value of 2 where C is the square in xy – plane with vertices (1, 0), (–1, 0), (0, 1), (0, –1) respectively is -
A –2
B 4
C 0
D 2
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Correct answer: 0
Q08. Evaluate () ∫ 4 C x x + xy y ∂ ∂ ∂ ∂, where C is the triangular curve consisting of the line segments from (0, 0) to (1, 0), from (1, 0) to (0, 1) and from (0, 1) to (0, 0).
A 0
B 12
C 1/6
D 1
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Correct answer: 1/6
Q09. For f (x, y) = x2 y – y3, which one of the following gives the corresponding gradient vector field?
A x2/i
B 2xyi + (x2 – 3y2)j
C xi + (x2 – y2)j
D (x3 – y2)j
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Correct answer: 2xyi + (x2 – 3y2)j
Q10. If f (x, y, z) = xsin yz, find the gradient of f at the point (1, 3, 0).
A (1, 0, 3)
B (1, –1, 3)
C (0, 0, 3)
D (0, 0, 0)
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Correct answer: (0, 0, 3)
Q11. Consider f (x, y) = xey. At the point (2, 0) what is the maximum rate of change?
A 5
B 4
C 1
D 0
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Correct answer: 5
Q12. A unit vector, which is normal to the surface x2 – xy + z 2 = 1 at the point (1, 1, 1) is–
A i– j 2k 6 ∧ ∧ ∧ +
B i j– 2k 6 ∧ ∧ ∧ +
C i j 2k 6 ∧ ∧ ∧ + +
D i– j– 2k 6 ∧ ∧ ∧
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Correct answer: i– j 2k 6 ∧ ∧ ∧ +
Q13. If r r, r r r ∧ =, then div r ∧ is equal to –
A o
B –1
C 1/r
D 2/r
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Correct answer: 2/r
Q14. Value of S ˆ F.nds ∫∫, where 2 F 4xz i– y j yz k ∧ ∧ ∧ = + and S is the surface of the cube bounded by x = 0, x = 1, y = 0, y = 1, z = 0, z = 1 is–
A 1
B 3/2
C 3
D 5/2
Show answer
Correct answer: 3/2
Q15. If the vector () () () F x 3y i y – 2z j x – az k ∧ ∧ ∧ = + + + is solenoidal then a is equal to –
A 1
B –1
C 2
D –2
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Correct answer: 2
Q16. If a and b are irrotational vectors then div () × a b is equal to –
A 1
B 2
C 3
D 0
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Correct answer: 0
Q17. If V is the volume enclosed by a closed surface S and ˆ ˆ ˆ F xi 2yj 3zk = + + then the value of s ˆ F.nds ∫ is
A 3V
B 4V
C 6V
D 5V
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Correct answer: 6V
English UPPSC GIC 2021 UPPSC Asharam Paddhati 2021
Q18. If F is a vector point function and S is an open surface bounded by a closed curve C, then the tangential line integral of F along C is described-
A By Green's theorem
B By Stokes' theorem
C By Gauss's theorem
D By Leibnitz' theorem
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Correct answer: By Stokes' theorem
English UPPSC GIC 2021 UPPSC Ashram Paddhati 2021
Q19. If ˆ ˆ ˆ r xi yj zk = + + and r | r | = then the value of curl () n r r, is-
A 0
B n rn-2/r
C n rn-1/r
D (n + 3) rn/r
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Correct answer: 0
English UPPSC Ashram Paddhati 2021
Q20. If S denotes the surface of the cube bounded by the planes x = 0, x = 1, y = 0, y = 1, z = 0, z = 1 then the value of normal surface integral of ˆ ˆ ˆ 3 2 F = (x – yz)i – 2x y j+ 2k over S is
A 1
B 1/3
C 1/5
D 1/6
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Correct answer: 1/3