Civil Engineering - Online Test

Q1. The sum of n terms of the series 4 + 44 + 444 + .... is
Answer : Option C
Explaination / Solution:




Q2. Let M4 = I, (where I denotes the identity matrix) and M ≠ I, M2 ≠ I and M3 ≠ I. Then, for any natural number k, M-1 equals:
Answer : Option C
Explaination / Solution:


D is not correct

Q3. Given the following statements about a function f : RRselect the right option
P: If f(x) is continuous at x = x0then it is also differentiable at x = x0.
Q: If f(x) is continuous at x = x0then it may not be differentiable at x = x0.
R: If f(x) is differentiable at x = x0then it is also continuous at x = x0.
Answer : Option B
Explaination / Solution:

We know that every differentiable function is continuous but converse need not be True

Q4. Which one of the following is a property of the solutions to the Laplace equation: Δ2f  = 0
Answer : Option A
Explaination / Solution:
No Explaination.


Q5. Consider the plot of f(x) versus x as shown below.

Suppose  Which one of the following is a graph of F(x)?
Answer : Option C
Explaination / Solution:

Since the integration of an odd function is even in this logic A and B cannot be the answer as they are odd functions. However both C and D are even functions but the integration of a linear curve has to be parabolic in nature and it cannot be a constant function. Based on this Option C is correct.

Q6. Consider a two-port network with the transmission matrix:  If the network is reciprocal, then
Answer : Option D
Explaination / Solution:
No Explaination.


Q7. The Laplace transform of the causal periodic square wave of period T shown in the figure below is
 
Answer : Option B
Explaination / Solution:



Q8. Let U and V be two independent zero mean Gaussain random variables of variances 1/4 and 1/9 respectively.  The probability  is
Answer : Option B
Explaination / Solution:
No Explaination.


Q9. Let A be an m × n matrix and B an n × m matrix. It is given that determinant (Im + AB) = determinant (In + BA), where Iis the k ×  identity matrix. Using the above property, the determinant of the matrix given below is
 
Answer : Option B
Explaination / Solution:

Consider the given matrix be

From the given property


Q10. A system described by the differential equation   Let x(t) be a rectangular pulse given by

Assuming that y(0) = 0 and dy/dt = 0 at t = 0, the Laplace transform of y(t) is 
Answer : Option B
Explaination / Solution:
No Explaination.